Leo went home to his parents' house because he hadn't seen Erren in two days. He didn't want to make Erren suspicious and instead wanted to go back to his own house.
His parents' house was quiet. It was late and of course they were all asleep. Leo hoped Erren was asleep too, because he didn't tell him he was coming back here.
As he was about to enter the room, he stood up, startled. A silhouette of two people having sex shocked Leo into silence. He didn't know why... there were two people having sex in his parents' house.
His body immediately stiffened and he swallowed. The two people didn't even know he was there because it was dark. But Leo was ready to catch them both red-handed.
CLICK!
He flipped on the light switch, making them immediately stop what they were doing. Erren, Leo's wife was shocked. She, with her naked body exposed and her pregnant belly growing, was having sex with her own cousin!