...are barely able to pull out in time

Fucking Miranda's mom is one thing, taking the risk of getting her pregnant it's another.
It would mean a complete different level of troubles for you.
But it's not common sense that saves you, rather plain survival instinct.

Slippery, coated with her juice, you try to slip your cock out of her gripping pussy the split second before causing a disaster.
Almost too late.
Cum splatters all over her gaping slit, suddenly empty, but still yearning, leaving you with you with the unsettling impression to have already done damage, before you manage to drag it upwards and smack it between her cheeks, thick ropes flying over her back, up to her shoulders, staining her shirt.
As the intial moment subsides, you mechanically rub you glan on her soft sweaty butt, plastering it, letting your cum pool in its crack.

Holy shit ...

Cat's breath is ragged, you feel her shuddering, and she's glaring at you through the mirror.
You have no idea when or even simply if she as come herself too, but that's not exactly the first thing you should worry about now.
Barely able to resist the the temptation to smack that ass, you step back, so to have a better look at the mess you've made.
Your cum is dripping down on the tiled floor, but pretty much all of it is splattered on Cat's back, glazing her buns.

"You have no idea of what you have done, young man." She hisses angrily , struggling to stand up, turning her head back over her shoulder to you.