Of course it is!

"Your ass you say?" Jack leers down at her, squeezing those young breasts of hers a little tighter, causing her to wince in pain.

"Ah, those are a little tender, Jack." She says with a grunt, her nipples thick and hard, visible through her thin shirt. "I'm still nursing you know..." And a bit of milk does leak through the top. He grins at that, and finds her nipples, squeezing them harder to get her shirt nice and milky. She whimpers, but just lets him do it.

But, back to her ass! He lifts her skirt now, seeing that she has a pale and beautiful little butt, clearly displayed thanks to the bright red thong she is wearing underneath. "Hoping someone would get a peek down here?" He grins, his cock already raging hard under his kilt, and snaps her thong, causing her to eep at the sudden pain.

"Well, I do have a boyfriend you know, gosh." She gives her ass a bit of a wriggle, and then can't help but blush. "Uhm, Jack? Uhm, I don't wanna sound rude, but, if you're going to fool around back there, you're going to use lube, right?"