Mei and Yamato's relationship starts at the begin of the series, when, instead of kicking Nakanishi, Mei ends up doing that with Yamato. The boy is not mad about what happened, and instead, his interest towards Mei becomes genuine. He tries to talk with her everytime he can and, in order to keep in touch with her, he gives Mei his number, so that they can comunicate in a simpler way. The girl is not interested in these kind of things because she had some traumas when she was a little girl and doesn't trust the others. But anyway, in a moment in which a stalker was trying to follow her, she calls Yamato that dashes in order to save her: since he wants to let the stalker understand that he has to go away, Yamato kisses her letting him understand that she's his boyfriend. Now, Mei is safe, but she's fairly embarassed because a boy kissed her. At the begin she is kinda mad about this, but thinking about the "matter", she won'd admit it, but seemed happy of what happened. After that accident, Yamato tells her that she's his boyfriend and that now they can stay together. Mei doesn't want to be as a slave for him, even because he didn't asked either if she agreed or not, but she's forced to pretend that's like this.

    Thanks to Yamato, Mei's personality will improve day by day even with the few friends she will menage to do. Though she will always keep her determination and diffidence toward the others. Yamato will open his heart to her and will do everything he can in order to make Mei happy, but to be happy himself. Their bond will become always more solid and they will trust each other in any case. There will be times in which they will think that they're not good for the other, in which they will fight, but the key to clarify these misunderstandings is to talk. Both Mei and Yamato do their best to be sincere with the other, but since they really love themselves too much, they end up to be jealous at times.