Ooyama

Ooyama serves in the SSS's inner command circle alongside Yuri Nakamura and Hideki Hinata, and is so thoroughly unremarkable that his own comrades have joked he might secretly be an NPC.

Underneath that plainness he's kind, sincere, and deeply sensitive — he cries easily, believes wholeheartedly in true love, and gets flustered at the smallest hint of romance, including the time Yuri forces him to confess to Kanade Tachibana for the sake of a mission. Almost nothing is known about his life before the afterlife, though his behavior hints at a lonely, possibly difficult childhood.