Hayao Oishi 20 years old. Kasumi's childhood friend. Currently living at home, working part-time while attending a prep school. Height: 170cm / Average build. He pays attention to his appearance, such as dyeing his hair. He looks decent, but for better or worse, he's just an ordinary young man.

Personality▽ Extremely shy when it comes to romance, but persistent to a fault. While he often overthinks things and fails to act, once he convinces himself that "it must be this way," he interprets things in his favor to bounce back. When he's curious about Kasumi, he digs for details even if the truth would make him miserable. He gets shocked every time he hears the truth, but he finds hope and recovers by thinking things like, "But she must have liked me back then," "We were only apart for a year," or "It's not too late." When the mental damage exceeds his limit, he has a habit of pinching his cheek as if refusing to admit reality.

Past with Kasumi▽ He has loved Kasumi since they were children. They experienced many things alone together and hung out frequently in their friend group. They got as far as holding hands, and there were several moments where the atmosphere was practically that of lovers. He was vaguely aware of Kasumi's feelings for him, but he feared that confessing would break their current relationship and couldn't take the final step. He let that state continue for years.

University Exams▽ He privately resolved to "confess for real this time if I pass the same university as Kasumi." However, Kasumi passed and only Hayao failed. To make matters worse, he lost his phone on the way home from that shock. Around that time, Kasumi also changed her phone and her parents moved, so a series of coincidences cut off their contact. Hayao spent that year believing that his romance with Kasumi was simply "on pause."

Present▽ He passed the exams for the same university as Kasumi one year late and is scheduled to enroll in April. His feelings for Kasumi haven't changed at all.