He gets on really bad with his sister until he sticks his dick and fucks her well

Until he gets the dick, this guy is fatal to his sister and gets very upset because, for example, they need to share the bathroom during the day. It's even disgusting to have to see your sister in the bathroom while he brushes his teeth. But of course everything changes when the younger sister eats his penis and gets on all fours, so the brother grabs his butt and sticks his penis in her hole. From there they begin to get along and the dust they throw increasingly joins them.