Hungry college student Kengo's first time is with a married mature woman.

Misako's husband hasn't touched her for years.
She's a loving mother and wife but she also has needs...
and at 37 years old she's in her sexual prime.

She lets Kengo chase his own ambitions,
even as she wishes to protect her status as a chaste family woman.
Those two desires conflict hardest when the young man's
touch awakened things she'd never felt before.

Together they explore all kinds of mania.
Misako's son becomes a party to their lovemaking,
joining a literal orgy party, and as a couple
Misako and Kengo escale sex to new heights---

[From DLsite English]