One night and two days of 1 night and left alone by my wife's sister who suddenly came over

My wife is going back to work for birth. Tomoya was about to go to a pachinko parlor, which is normally prohibited, to enjoy living alone for the first time in a while. Then my wife's sister Mao came to help out with the housework. He was grateful that he cleaned up the messy living room, but for some reason, Tomoya was strangely shown his panties and breasts. My lower body couldn't help but react to the intense sexiness that wafts out from Mao...