A serious, intelligent character of the series, he becomes the vice president after losing to Ui Wakana's love campaign and her extroverted personality. She soon moves into his apartment and informs him that their parents set them up in an arranged marriage while three of them were drunk.
At first, Hayato is opposed to the idea of a boy and girl living together and is upset how the arranged marriage isn't respecting their feelings. He also has trouble initiating kisses or other acts of romance or sexual pleasure. However, it is shown that once he has started, he becomes more sadistic and willing to engage with Ui.