Tatsuya is married and lives with his wife and his wife's mother. His heart is stirred by his stepmother's cuteness that he sometimes sees. One day, his stepmother buys an aphrodisiac cream. He tries it out and it works perfectly. Her nipples are hard and her vagina is ripe. The two of them can't stop themselves and end up in a forbidden relationship. Her juices are overflowing and he can't help but cum inside his stepmother, who is cute as she feels pleasure. The two become addicted to the pleasure and have sex in the bath, in the Japanese-style room, and on the bed... a lewd incest story that continues over and over again.