Takehiko Henmi

Takehiko Henmi  (辺見 武彦 Henmi Takehiko), also known as "Oniisama", is a favorite tutor of Nanako Misonoo, whom she asks to be her "Oniisama"—a trusted older-brother figure. He is a graduate student at Gakuin University along with Takashi Ichinomiya and Takehiko has aspirations to study abroad in Germany. Takehiko is actually Nanako's stepbrother, the son of Mr. Misonoo's first marriage, though he keeps this secret from Nanako so as not to air the family's dirty laundry. He was involved with Kaoru Orihara approximately two years prior to the series' start, though after she was diagnosed she ended their relationship. He is acquainted with the Ichinomiya family through Takashi. He appears to know of the situation with Rei Asaka, though if this information was revealed through Kaoru or Takashi is not stated.

Takehiko is voiced by Tesshō Genda.

Trivia

 * The name Takehiko means "military, martial" (武) (take) and "boy, prince" (彦) (hiko).