Master

Owner of the bar frequented by Tatsumi. He is related to the resurrection of the seven girls.

[Spoiler] During the second season, he is revealed as a deity, an incarnation of the "Saga Spirit"; along with his connection with Yuugiri. [/Spoiler]

[Spoiler] During the events of the spin of manga, he is introduced as the leader of the Saga Sagako Busters, so as Yamada Tae's adoptive father. [/Spoiler]