He does

"Wait what?" Rose asks in shock as she watches her brother rise from his seat, taking hold of the wet cloth his mother offered, a clear buldge appearing in his jeans.

"Are you serious?" Mike finally asks, glancing between his mother and his sister.

"You made the mess you can clear it up." Is all their mother says in response.

Very slowly Mike makes his way to his sister, kneeling at her feet, well aware of just how close his face is to her bare pussy, before he begins to slowly wash the oj off of her knees, slowly making his way up her thighs.