That all changed when he was nine, when both his mother and Amane were killed in a car accident. While Ryou was lucky enough to not be in the car when the accident happened, this still left him with his father as his only immediate family, a man who was getting increasingly obsessed with stories and rumours of a mysterious Egyptian artifact. This obsession came to a head in 1991 when his father went to Egypt to get his hands on that item, taking Ryou with him due to a lack of other options. Ryou, now ten and curious about what his father was doing, ignored instructions to stay in the hotel room and sneakily followed him out to the tomb where the item was kept.

This proved to be the single worst mistake of Ryou's life.

In the tomb, Ryou watched as a man named Shadi told his father to complete the test of wearing the item, an artifact known as the Millennium Ring, to prove he should have it. His father complied - only for the Ring to almost immediately start to reject him, causing the man to collapse to the floor. Terrified of losing his father, Ryou ran out of hiding to try and help, only to be asked by his barely conscious father where the Ring was. Thinking that getting the Ring would be helpful, Ryou picked up the dropped Ring -

- and was immediately accepted by it, the ancient spirit held within possessing Ryou and immediately using his newfound host to kill Shadi on the spot before attempting to kill the kids Shadi had been raising. From this point forward the Ring Spirit would take Ryou as his 'landlord', possessing him at will to do whatever he wanted with Ryou himself completely unaware of what was happening or why he kept having memory gaps. The incident at the tomb was so traumatic that Ryou completely blocked the events out of his memory, instead believing for years that the Ring was a gift from his dad.

Things continued to get worse from that point forward. Ryou picked up an interest in TTRPGs and creating miniatures/dioramas (especially a TTRPG called Monster World, which actively encouraged the use of miniatures on a board for play), but didn't get much chance to enjoy his new hobby before the Spirit started taking over during games to seal the souls of his friends and gaming buddies within their character minis and sometimes even within his dice to create rigged dice. This had the effect of leaving their bodies comatose and Ryou confused and frightened of why people kept going comatose every time he tried to play. Even worse, his classmates would inevitably start avoiding Ryou whenever this happened, forcing him to transfer schools several times in an attempt to get clean starts. Eventually he started shying away from playing Monster World altogether and, in 1996, moved out on his own, terrified that getting too close to others would only result in more people getting hurt.

Still, he had to attend school, so he transferred schools yet again, leaving his previous school to instead attend Domino High. Between his bad reputation at his previous school and Domino being closer to his new apartment, it was an easy choice. Ryou wound up in the same class as Yugi, Jounouchi, Anzu, and Honda, who eagerly tried to befriend him and even asked to play Monster World with him once they found out he was a fan, despite Ryou's caution.

However, things would not stay good for long at his new school. The gym teacher, a man named Karita, intercepted Ryou in the halls during his first day and deliberately brought up his poor reputation at his previous schools, telling him to cut his hair if he wanted to be accepted. On top of that, Ryou had been experiencing chest pains ever since meeting Yugi, and had started hearing a mysterious laughter with no seeming source. Scared, he tried to warn Yugi and co off of interacting with him by telling them about the comas, hoping they would avoid him and he could just get by alone. Things continued to get worse that night, with the Ring Spirit finally revealing himself and what he'd done to Ryou's friends to his horrified 'landlord', and in the process took the step of embedding the spikes of the Ring into Ryou's chest to keep him from taking it off. He then possessed Ryou and proceeded to steal Karita's soul as vengeance for trying to make Ryou cut his hair.

Terrified, Ryou stayed home from school the next day, only to have Yugi and co literally show up on his doorstep asking to play Monster World with him. He tried to warn them off, desperate to keep the Spirit from hurting them, only for the Spirit to possess him once more and invite them in to play. However, things were different this time around; as it turned out Yugi's Millennium Puzzle also contained an ancient spirit, that of a nameless pharaoh, who was able to hold out against the Ring Spirit's cheating. On top of that, thanks to a lucky strike on the boss monster by Jounouchi, Ryou was able to retake control of his left hand and start fudging numbers and dice rolls just enough to hinder the Spirit in his goals. He wasn't able to do this for long, as the Spirit stopped him by impaling his hand on the top of a model tower, but it did buy some time for Ryou's new friends to fight back.

In a fortunate turn of events, Ryou had a level thirteen White Wizard character that he'd played so much that the figure had gained a piece of his soul, allowing the White Wizard to step in and assist as well. This became especially fortunate as Ryou ended up allowing his soul to be destroyed in a last ditch effort to stop the Spirit from TPKing the whole table, saving everyone but killing Ryou in the process. The White Wizard, with help from the 'other Yugi' on the dice roll, was able to cast a spell to transfer his piece of Ryou's soul back, reviving Ryou at the cost of the White Wizard being reverted to level one.

This marked a slight turn in Ryou's fortunes. Now aware of the true nature of the Ring and finally able to have friends again, Ryou started to warm up to being around others and even joined his friends in traveling to the Duelist Kingdom tournament, partially to support Yugi and Jounouchi and partially in hopes of learning more about the Millennium Items. This curiosity towards the Items also influenced his choice to keep the Ring despite everything that had happened. After all, if he just didn't put it on again, then the Spirit wouldn't be able to do anything, right? And the Spirit had been quiet ever since that Monster World game, right?

As it turned out, the Spirit was biding his time, waiting for the opportunity to strike. That opportunity came during Duelist Kingdom, when Ryou and his friends were trapped in a puzzle room with two doors, under the claim that only one of the doors actually led out. The Spirit claimed to Ryou that he had turned good and that he not only wanted to help, but knew which door was the correct one. Ryou, distrusting the Spirit but desperate to do something and aware of the time pressure of the tournament, chose to take the risk and put the Ring back on.

From this moment the Spirit began manipulating his 'landlord', letting him think he really had turned good and giving no indication he was still evil as he pursued his goal of collecting all seven Millennium Items. Ryou, for his part, didn't tell his friends he was wearing the Ring again and slowly came to believe that maybe this was the right choice. Even after the Battle City tournament, which Ryou spent most of being controlled by both the Spirit and Malik at the same time and came out of with an injured left arm, Ryou still insisted on finding and reclaiming his Ring afterwards out of his belief that the Spirit was good. It probably didn't help that the Spirit had been encouraging Ryou to work on a highly detailed diorama of the Ancient Egyptian kingdom, which he put some of his best work into.

Then came the trip to find out the true name of the pharaoh tied to Yugi's Puzzle.

Told by a man named Bobasa that he had to test the friend group for evil with the Millennium Scales before they could go, Ryou consented, only to be the only one in the group to be declared 'evil'. Hurt but not wanting to hold up the group, Ryou claimed he was fine not going and left, only to end up crying once he was out of sight. And to add insult to injury, the Spirit picked that moment to take control, taking the chance to start his Shadow RPG using the diorama he'd gotten Ryou to build, all in hopes of reviving the demon Zorc Necrophades and rewriting history.

The Spirit failed and was beaten once and for all, and Ryou woke up some time later to find out that the Spirit he'd thought was now good was actually evil all along. It hurt him, to find out he'd been had for so long.

And unbeknownst to Ryou, Bobasa was actually the ghost of Shadi, the very man who had witnessed Ryou be possessed for the first time and became the Spirit's first victim. Awkward, that.

Now freed from the Spirit for good, Ryou joined his friends in a trip to Egypt to return the Millennium Items to the tomb they came from and see the pharaoh, now known to be named Atem, off to the afterlife. In that moment, Ryou thought that the Ring would no longer cause trouble for him, and with his high school graduation coming up on the not so distant horizon, prepared to move on with his life.

Of course, things weren't that easy. Shortly before his graduation in the spring of 1999, a teen named Aigami showed up, seeking revenge against Ryou for the death of Shadi eight years prior. Aigami, who turned out to be one of the kids the Spirit had tried to kill the day Ryou first got the Ring, used the powers of his Quantum Cube to force Ryou to recall the memories he'd buried, deeply rattling him and causing Ryou to try and explain it was the Spirit who did it before tearfully apologizing anyways. In this moment, with his target crying and apologizing, Aigami wavered-

-Only for his friend Mani to show up, under the control of the Millennium Ring Ryou thought was gone. Mani attempted to kill Ryou, and succeeded in sending him to another dimension, one where Ryou would have been erased from existence had he stayed too long. Thankfully, he was rescued before he could be completely erased, but given how long he spent in the other dimension it would have been a close call.

Graduation came not long after this. Ryou finally got to finish high school, and the last we see of him in canon is him and his friends seeing Anzu off at the airport as she left to go become a dancer.

Ryou is very genuinely a nice, if somewhat quiet, guy at heart, caring immensely for his friends and family. In fact, he cares about them to an almost self sacrificial level, putting their needs ahead of his own if he thinks that's what he has to do. This can result in Ryou having trouble with pushing for what he personally wants if he believes other people's needs are more important than his, something that has led to him not pushing hard enough for his own desires sometimes. Examples of this range anywhere from moving out on his own to prevent any more people close to him from going into the mysterious comas that had been happening at the time, to claiming he was fine with being left out of the Memory World trip after being told he was Too Evil To Go (he wasn't fine and ran away crying, not to mention that it was the presence of the Ring that got him deemed Too Evil To Go), to sacrificing his own soul in a last ditch effort to stop the Ring Spirit from killing his friends (he got better, but had no idea he would come back from that at the time). This level of caring also leads him to write letters to his dead sister, telling her about his life and how he's been doing.

He's also incredibly determined when it comes down to it, putting up quite the fight against the Ring Spirit in his intro despite being possessed and largely unable to stop the Spirit from trying to steal the souls/kill off his new friends via a heavily rigged TTRPG game. This fight included using what little control he had to fudge several dice rolls in favour of his friends and type out a message to the Spirit on his laptop just to tell him that he's fighting too, and ultimately escalated to the aforementioned last ditch effort of sacrificing his own soul to stop the Spirit.

This kindheartedness, while very genuine, also has a secondary motive; Ryou is trying to prove he's a good person unlike the Ring Spirit. He figures that maybe if he's nice enough, helps his friends enough, backs down when told no and doesn't make himself difficult and works to fix what the Spirit did while possessing him, then people will stop blaming him for the Spirit's actions/calling him evil. Ryou will claim he's fine and smile for his concerned classmates after the bully of a gym teacher brings up his 'troublemaker' status at previous schools to try and make him cut his hair, he'll smile and say he's okay not going when told by Bobasa he's 'too evil' to help Atem recover his memories for the sake of not holding up his friends only to end up crying the second he's out of sight, he'll apologize for the Spirit's actions to Aigami when confronted over the death of Shadi rather than explain his experience with the Spirit, all to prove he's good.

With all this, you'd think Ryou is the straightforward angel to the Ring Spirit's devil, but that's not quite true. Ryou has a mischievous/trollish streak just under the surface, which comes out during the Battle City arc when he tried to get his friend Jounouchi to look at his occult themed Duel Monsters deck despite knowing that Jounouchi was afraid of the supernatural. This streak came out again at the end of the arc when he helped Mai briefly fake her own death as a prank, with Ryou finding the whole thing funny when the 'death' was revealed to be a joke. He's also got a strong interest in the weird/creepy/occult, leading him to do things like writing the earlier mentioned letters to his long dead sister and building the aforementioned occult themed Duel Monsters deck for himself with a heavy focus on cards like Dark Necrofear and Spirit Message. These traits seem to generally only come out around people he's close to and comfortable with, as we never see him act this way to anyone outside of his friends.

Ryou is also notably curious, expressing interest in learning more about the Millennium Items after finding out the Ring was haunted. However, this curiosity also gets him in trouble sometimes, most notably when, as a kid, he followed his father to the tomb the Millennium Ring was being kept in out of a desire to know what he was doing, only to end up being claimed as the Ring Spirit's unwitting host. His curiosity also backfired on him when his choice to keep the Ring out of curiosity allowed the Spirit to manipulate him into wearing it again.

This brings us to the Millennium Ring and why Ryou kept it for so long. Part of why he kept it after realizing it was haunted was likely his own curiosity into the Millennium Items, along with his general interest in the occult. But a major influence was a combo of the Ring Spirit's manipulations and Ryou's own desire to help others no matter the cost to him. During the Duelist Kingdom arc, the Spirit is shown manipulating Ryou into putting the Ring back on by claiming that he'd turned good and knew how to get out of the puzzle Ryou and his friends were currently stuck in. Ryou, desperate to help his friends escape, chose to put the Ring back on, despite distrust in the Spirit at the time. This paved the way for the Spirit to further manipulate and take advantage of Ryou, hiding his true actions in the memory lapses the possessions caused and encouraging him in his diorama building hobby so Ryou would think the Spirit really was trying to be good. Obviously, this was all untrue, and the Spirit was as evil as ever with Ryou once more the unwitting host now being used to prepare the diorama for the final Shadow RPG.

(And perhaps there was a bit of wishful thinking on Ryou's side; he knew to some degree that he shouldn't trust the Spirit, but the idea of the Spirit being good was easier to handle than dealing with a known evil entity possessing him at random to do whatever he wanted.)

However, by the events of Dark Side of Dimensions, Ryou is now permanently freed from the Ring and seems aware of the Spirit's true nature, as shown when he desperately tried to explain to a vengeful Aigami that the Spirit's actions weren't his own. He also seems to have some degree of guilt over the Ring Spirit's actions, as despite trying to explain what happened to Aigami, he ends up tearfully apologizing anyways. His confrontation with Aigami also reveals that Ryou apparently buried his memory of when he first got the Ring as a child and didn't want to remember it, forcing Aigami to make Ryou (painfully) recall what happened that day.

All in all, Ryou is a very unfortunate young man who manages to stay the polite, kindhearted guy he is despite everything that happens to him in canon.

-He has a mild caffeine addiction, fueled by both his habit of staying up late to work on TTRPG scenarios/miniatures and, back when he had the Ring, the Spirit's habit of possessing him at night to pursue his own goals. Both of these situations generally leave Ryou exhausted the next morning, resulting in him relying on (sweetened) coffee to keep himself awake.

-Ryou speaks Japanese fluently (it's his birth language), and can speak conversational level Egyptian Arabic thanks to the time he spent living in Egypt before he moved back to Japan.

-Amane was two years younger than Ryou. She was seven when she died. (I use Ryou's season 0 anime design, with slightly darker blue hair, as reference for Amane).