Kyonyû hatsujô nurse (2000)

Tsubomi is a nurse at a sex clinic run by Kawasaki. One day, a young woman named Sango visits the clinic, asking for help to restore the libido of Manabu, the middle-aged man she lives with. Tsubomi immediately pays Manabu a visit and uses her techniques to bring him to ecstasy. Manabu had unexpectedly succeeded as the second-generation boss of a yakuza clan, but the organization went into rapid decline; unable to bear the situation, he went into hiding and began living with Sango. Then, someone began targeting him...