Things end pretty quickly

Jack whimpered as he felt his mother's tight sphincter wrap around his throbbing pole. Inch by inch, she slowly lowered herself down. Maybe it was as she said; due to his size. Or maybe, she was enjoying the sensation just as much as he was. But she made sure to go slow.

Talking about time, not much had passed. There was still the sounds of the water lapping at the sides of the tub, and also the breathy grunts from two occupants. Speaking to here, the scene looked so erotic.

Jack's cock was fairly large now, being 13 inches, so it stood a little out of the bath water. His mother hadn't really filled the tub up too far, just enough to cover the legs and lower torso. She probably did it this way so Jack could still see what he was doing.

"Ohhh~ So..BIG... ummm... Jack, let's stop here for a sec..." Breaking the silence, his mom paused her body so she was just out of the waters reach.

"Sure... Mom..."

Jack would've agreed to anything at this point. His main focus was the tight grip his mother's ass had on his cock. But being stopped so abruptly made him reach out his hands to steady himself, right on his mother's creamy backside. He gave it a tentative fondle.

"Mmmm.. Good... Hold me steady..mmmm?... Jack, can you continue?" Feeling his cock twitch inside her, she wanted to give him a few seconds to settle. She enjoyed the way he kneaded her ass, distorting it into different shapes. If she was really being honest here, she would've preferred he smack it too. But that was too much to ask of her son right now.

"Yes.." Jack spoke in a barely restrained manner, clearly exercising great resolve.

Hearing his approval, she resumed going down on him. As she entered the water, the speed of her lowering got quicker and smoother.

"This must've been the effect she was talking about", Jack thought as he felt her getting closer. Looking at his cock getting buried in her ass, Jack marvelled at how it could fit in there. Being that his cock was definitely wider at the base. Was her asshole stretching to fit like she said? But it still felt so tight.

"You... feel... it...right?" His mother spoke, shuddering and panting slightly.

"F...F...Feel?" Hearing his mother speaking, Jack replied uncertainly.

"Well... As I bottom out, my sphincter expands to accommodate the intrusion. This being your cock Jack. Can you see it?" Turning her head back, she tried to look at Jack as she spoke.

"Yes mom, I can see it going in..."

"That's good..mmmmh"

With one last push, Jack felt his mother land on his lap. Small ripples surfaced on the water. Now with the globes of her cushy ass touching his pelvis, Jack rested his hands on her sides, which drew a contented sigh from her.

"Now to the fun part. Seeing that I've adjusted, we can begin to bounce on your cock. Should we do that Jack, or do you want me to stop?"

Having run through things with him, his mother didn't want to pressure him. With time, he'll understand.

Hearing no response, she was just about to get out of the tub when she felt him pull her back and piston. "Ooh... Okay...mmmh"

It was needless to say, being worked up made Jack take the initiative.

Using the tub's surface, he moved his lower half in and out of his mother's body with smooth glides. It wasn't long before he felt himself cumming. White hot spunk coated his mother's bowels as they both cried out. He couldn't believe he came in his mother.