Season 1

Shiki arrives at the Orifushi household, and reunites with the three sisters Akina, Natsumi and Mafuyu, who are his childhood friends. He soon starts going to Akina's school, where he learns she is the school idol, and has a strange encounter with Suzuran, one of Akina's friends.

When rushing to the school toilets, Shiki accidentally bumps into Suzuran, who brings him into the ladies restroom and has sex. Later that day, Shiki ends up having group sex with Midori and Suzuran in the infirmary, when Midori insists that Shiki break up with Suzuran (though this is a misunderstanding), and in return Shiki can do whatever he wants to Midori.

Shiki has sexual intercourse with all three Orifushi sisters dressed up as maids, which they call "service". The Min-Min Ice Creamery service which Natsumi runs has problems, causing Natsumi to doubt herself. She makes Shiki work hard while, her, Akina, and Mafuyu are at a festival.