Ok, the most obvious relationship Yuki has is with Shuichi. They met one night when Shuichi's lyrics flew off from his hand and was caught by Yuki. Yuki insulted it and Shuichi wouldn't stop pursuing it. He ran in front of Yuki's car to demand an explanation, and inadvertently falls in love with him somewhere along the way. As far as I know, Yuki wasn't a bisexual, at least that was unknown to him until Shuichi showed up. Then again, Shuichi wasn't a homosexual in the beginning either. Yuki told Shuichi he wasn't interested in other guys, but does kiss him at the end of the first episode. Shuichi's had some issues with loving Yuki as well, he confessed to Hiro that it doesn't feel right, but Hiro said he can't help who he falls in love with.^_^ It's interesting how Yuki and Shuichi are able to live with each other despite the fact that they are complete opposites. But then again opposites attract.^_^

To Yuki, Shuichi is an annoying little brat but cute at times. To Shuichi, Yuki's the greatest thing since sliced bread. :P Shuichi can get very hyper at times and annoy Yuki, causing Yuki to say something he doesn't mean and attempting to end their relationship. Shuichi tends to be overly dramatic at times, shouting out "Yuki's MINE!" during their first Bad Luck concert, crashing through the walls to 'protect' Yuki, and even crossdressing because he thought that's what Yuki wanted. Yuki on the other hand does everything he can to get rid of Shuichi, even telling him that he's killed a man once to try to turn Shuichi away. This is mainly because Yuki doesn't want to hurt Shuichi in anyway, and he thinks that his relationship with Shuichi will taint Shuichi's reputation, as Tachi threatened to do. Yuki thinks staying away from Shuichi will be best for the hyperactive nineteen year old. When all of Yuki's attempts to get rid of Shuichi doesn't work, he turns away himself and moves away. Nevertheless Shuichi manages to find him time and time again, even when Yuki goes to New York. Shuichi stampedes around Japan looking for Yuki and trampling everyone's houses. *sweatdrop*

Yuki and Shuichi have been through rough times together, but in the end, they managed to work it out despite Tachi's threats and their own differences. Because of Shuichi, Yuki was able to overcome the pains of his past and get over what he's done. At the very end, he decides to returns to Shuichi after visiting Kitazawa's grave.