C-1974 - Please, make me pregnant... Secret pleasure guide for wives struggling with infertility

Wives struggling with infertility visit a master of 'bedroom arts' in a hot spring town. Under the guise of fertility coaching, a series of lewd techniques ensue. The first wife is teased in the bath, leading to climax, followed by intense intercourse. The second, a stunning dark-haired beauty, moans as her erogenous zones are stimulated to boost hormones. Finally, a slender, quiet wife gives in to every command, reaching ecstasy while riding the master.