Shinogu, Yuuma's older male cousin, is the reincarnation of Serena's overprotective older sister Smyrna. Like Keidai, he retains memories of his past life, and hates Keida for abandoning Serena during the volcanic eruption. He has an aversion to hot weather because of his strong and vivid memories of the destruction of Pompeii. He began working as a student teacher at Keidai's high school after Yuuma's family moved to town. Shinogu despises males except for Yuuma, and is a womanizer who is unfailingly nice to girls. As Smyrna was best friends with Lady Aglaia, Shinogu was extremely happy to meet Aglaia's reincarnation, Shuna.

Spoiler

Shinogu holds a grudge against Souichi Mikage because in his past life as Delos, he betrayed Aglaia.

(Source: Wikipedia)