Kazuya Hasegawa, an office worker who had been drinking with his colleagues, suddenly found a signboard of a massage parlor on his way home.

He was drunk and it was his payday, so he took the plunge and entered a massage parlor for the first time.

Kazuya was massaged by Yuka, the owner of the massage parlor, and when he learned that the parlor also offered sexual services, he fell in love with her techniques.

[From official site]