Kazuki, a virgin, can't help but stare at his friend's sexy mother who lives next door, and get aroused... One day, Kazuki witnesses the woman and his friend getting cozy with each other at the front door, even though they are mother and son. Noticing Kazuki's awkwardness, the woman shows him her naughty appearance, and when Kazuki's virgin dick gets aroused and erect, she takes its virginity.