My wife's mother secretly works at a super-high-class creampie specialist mature soapland: "Please keep it secret from all of my family..."

Toshiki is addicted to gambling in hiding from his wife. Today, a rare large win in boat racing, and as a reward for myself, I headed out to a super-high-class soapland... and the mother of my wife appeared there! "What are you doing, stepmother!?" "Toshiki-kun!?...Please keep it a secret from everyone!" Toshiki's mouth open to her stepmother's true identity, which she never imagined. "Um... if you keep a secret... I'll give you plenty of service." If you're invited by the slender body that you've been interested in for a while, then letting your body go... your super lewd technique will lead you to a state of orgasm!