Groping and scrubbing...

The old man's fat body occupied most of the bathtub, leaving little space for Mei's petite frame and making it so that physical contact was unavoidable.
Despite that the girl still attempted to squeeze herself in the little free space away from him as she walked in... but as she was one leg in the bath Old Mo grabbed her arm and "Wh-kya!" pulled her over, making her land on his body and grabbing her so she'd stay down.

"What are you getting all prissy for?" the man chided, both his hands swooping in from the sides to grab her large breasts and knead them with gusto, his words and the suddeness of his action and sexual harassment leaving the perplexed girl at a loss for words, the blush on her face the only indication of her embarassment and hesitance about all of this "Uhm... your hands..."

"What about them? Your tits won't be washing themselves, and i've already neglected their importance during your treatment so i thought i'd give them the focus they deserve" he excused his **** behaviour with some nonsense and in the meantime his hands didn't even stop fondling her funbags... if anything, he even began to up his game as he began to tease her nipples, making her gasp in the process.

Washing? Medial treatment?
All a bunch of crap. He only cared about playing with her tits, poking some special pressure points while at it to ready her body for more.
He was quite skilled at this and soon enough her nipples diamond-hard as he rolled them between his fingers, his ministration slowly but surely affecting Mei, the girl biting her finger in an attempt to not show how much her body was reacting to his touch, forgetting to mind how long this unappropiate behaviour had been going on!

And how could she keep track of time, when she was on the verge of an orgasm from just her tits?
What she didn't know though was that her orgasm wasn't cumming not because she managed to endure, but because he was purposefully holding back and never letting her reach peaking point!
He didn't want her to cum and be satisfied... he wanted her needy, needy for the climax she knew he could give, the more needy she was the morely she was to overlook the small liberties he wanted to take and maybe he could even push past some limits!

And therefore he kept pushing her soft spots to further heat her up while never giving the satisfaction she was slowly but surely coming to crave, purposefully putting less effort on her tits whenever she was about to cum and playing a pretense of washing the nearby parts of her body as an excuse... as expected, after keeping her on the edge for so long she became quite obedient and din't even mention about how hard his dick felt against her ass, silently allowing him to keep his meat betweeh her ass-cheeks and spreading her legs without even being asked to when she felt his hand move down from her breasts and caress it's way down to her navel.

"Good girl, let's get you all nice and clean"

She silently nodded and while she might never admit it, her body was craving his touch and her pussy felt especially tingly at the prospect of finally get some action... the sweet gasp escaping her upper lips as he caressed her lower ones was a clear indication of how much her body was reacting to the old man despite her mind hating the idea of him having so much authority over her and using him to achieve a level of intimacy only Ren should be eligible to.

"Ren that brat, he really filled you up" he commented, using a little trick he learned to get those young wives hot when seducing them during his quack treatments... usually the more they loved their men, the hornier they'd get when mentioning them while being unfaithful.
And Mei... considering how much she squeezed on the fingers scooping out his disciple's cum out her pussy, she was a prime example of such a clichè.

Therefore Old Mo didn't mind playing the concerned mentor commenting about his naughty disciple to his girl... in another context it might even be an hearwarming and wholesome scene, but the same couldn't be said if said concerned mentor was busy burying his finger into his disciple's girl while openly fondling her tits, both horny and naked in a bath...