내 새엄마가 바람을 피우다 걸렸어

Stepson accidentally discovers naked photos while trying to assist his stepmom with taking some pictures. And wouldn't you know it, there's she getting down and dirty with some mystery dude. When he finds out about her little secret, she begs him not to tell his dad about it. But since she knows how much he enjoys playing around, she offers him a deal - some private time in return for keeping quiet.