Atsushi begins a tutoring job for a rebellious girl named Arisa, but his professional life quickly spirals into a series of erotic encounters. After a secret tryst with the woman who hired him, Chidori, Atsushi forms an intimate bond with Arisa and is subsequently recruited by a neighbor, Nami, to tutor her daughter, Maya. The arrangement turns provocative when Nami encourages Maya to explore her sexuality with Atsushi, eventually joining in herself. Overwhelmed by the chaos, Atsushi realizes he is now deeply entwined with these women and cannot bring himself to quit.
After Atsushi is caught in a love triangle between Arisa and Maya, the two girls decide to share him, only for their secret to be exposed by Nami. Nami orchestrates a gathering that brings the entire household together, leading to a series of intimate encounters that include Aki and Chidori. Ultimately, the group embraces their unconventional arrangement, transforming Atsushi's tutoring sessions into a permanent, hedonistic family tradition.