Resistance[]
Ruri Kurosaki & Shun Kurosaki[]
Ruri is one of Yūto's close friend, though Yūto's feeling for Ruri is more than just friendship. Yūto first took interest in Ruri when he first saw her Dueling and then quickly developed feelings for Ruri the moment they were introduced to each other and both quickly became close since Ruri is his best friend's little sister. They are so close that they exchange knowledge about the decks they are using. So far, Yūto, who is usually calm and cool became embarrassed when around Ruri, blushing and confused of what to do particularly if Ruri is getting close to him. Ruri is also shown to return Yūto's feeling, developing feelings for him since their first meeting and she even made an intimate move to him while blushing shyly.
Yūto, Ruri, and Shun.
Shun is Yūto's Resistance comrade and best friend. Although there are disagreement between their ways on finding Ruri, they have a lot of faith and trust in each other. Yūto also refers to Shun as his best friend, protesting that the two did not run away from their homeland. He is also shown to have to keep Shun under control (sometimes with physical force) and even continued to do so after being merged with Yūya, such as when Shun angrily accused him of stealing Yūto's Duel Disk and Dragon. Shun also considers Yūto as his one and only best friend, though this didn't stop him from threatening Yūto when he felt Yūto was getting in his way of saving his sister. Shun is very concerned of Yūto's well-being, which was demonstrated when he wanted to assist Yūto in fighting Yūgo, and when he angrily accused Yūya of harming and stealing Yūto's Duel Disk and Dragon since Yūya had possession of the card. Shun understood Yūto's deep hatred for the Academia, and thus when fighting Dennis, he Duelled fiercely in his stead.
Kaito Tenjō[]
Kaito is one of Yūto's Resistance comrades. Kaito was a rival of Yūto and Shun due to their respective school's rivalry and had Dueled countless times against each other during their times as students. Yūto respects Kaito as rival, fellow Duelist, and a comrade once they joined the Resistance together. When seeing how much Kaito has changed during his absence, Yūto assisted Yūya in Dueling Kaito, wishing to soothe his anger and hatred and return his kindness that he once had. Hearing the reason of Kaito's change caused Yūto to regret ever going to Standard Dimension, thinking if he had stayed, he could have protected Kaito's family and his comrades, preventing Kaito from changing to the way he is now. Kaito also viewed Yūto as his comrade, getting angry at Yūya like Shun when he summoned "Dark Rebellion", thinking Yūya defeated and stole it from Yūto. At the same time, however, Kaito's grieve resulted him to cut all ties with his Resistance comrade, straining their bonds. Once Kaito returned to his senses, Yūto and Kaito recovered their friendship.
Friends[]
Yuzu Hīragi[]
Yūto and Yuzu.
Upon their first meeting, Yūto mistook Yuzu for Ruri Kurosaki. He began to grow protective of her until he discovered she was not Ruri. However, despite this knowledge, Yūto still watches over her, warning her not to get involved in their battle because he doesn't want her to get hurt and also told her that if she got involved, then he wishes for her to survive. Yuzu was initially skeptical and wary of Yūto, but eventually understood that Yūto was not a bad person, defending him when Masumi thought he was the one responsible for attacking Marco, and cleared up the misunderstanding between him and Yūgo.
Yūya Sakaki[]
Yūto and Yūya.
Although they've only met for a short period of time, Yūto immediately developed a trust in Yūya because they both believed the purpose of Dueling is to make people smile and have fun. Yūto truly wishes for this, which led him to sacrifice himself for Yūya from Yūgo's Dragon. He then entrusted Yūya with his "Dark Rebellion Xyz Dragon" and told him to bring Duels with smiles for everyones' future. Yūto grows to be protective of Yūya as shown when he merged with Yūya to help him defeat Isao who had cornered Yūya in his Duel. Yūya also grows to trust Yūto, having directly saw his memories, sensed his emotions and feelings after Yūto was absorbed into him. Yūya determined to fulfil their promise, which became one of Yūya's primary motivations to continue Duelling. As a result, the two formed a strong bond and have defended each other in many ways, such as Yūto defending Yūya from Shun's accusations and Yūya silencing Reiji when he was about to tell about the Xyz invasion because he knew how much it hurt Yūto and Shun. However, there have been times when Yūto's protective nature and hatred for Academia have gotten the better of him and caused him to betray his and Yūya's wish for peace and happiness by taking over Yūya and Dueling violently, which upsets Yūya greatly. By the time Yūya able to change Edo's heart, Yūto's confidence in Yūya returned. Since then, he opts to watch over Yūya and never directly interfere in his Duel, trusting him completely. His trust in Yūya has grown so much that Yūto willingly let himself to be influenced by Zarc, believing that Yūya will free him from the darkness.
Yūgo[]
Yūto and Yūgo.
Yūto initially had an antagonistic relationship with Yūgo ever since their first meeting. Their animosity towards each other was strong enough to make them act first before thinking further. This turned out to be a misunderstanding between the two of them. Yūgo mistook Yūto as Yūri, who kidnapped Rin, while Yūto mistook Yūgo as one of Academia Duelists when the latter challenged him instead of answering his question on their first meeting. After the misunderstanding between them are cleared and now they are residing inside Yūya, their relationship significantly improved and the previous hostilities between them were all forgotten. Both now willing work together to support Yūya, and Yūgo even gave his encouragement to Yūto when it was his turn to assist Yūya with Yūto accepting it.