Just watch for a while

Leaning against the doorframe, you watch your brother shoving his cock down Mom's throat. After a few more pumps he pulls out and backs up a little, still holding the back of her head.

"Open up," he grunts, jacking off a few inches from her face. "Take your medicine, Slut."

"I still don't like it when you call me that, Cassi--"

"Remember what we talked about. You know what makes me cum harder."

"I, um..." Your mother looks confused. "Lots of stuff makes you cum harder. What do you need?"

"Don't call me Cassidy. Talk dirty, call me--"

"Oh! Oh... Master." She looks a little bit disgusted, but continues. "Give me some medicine, please... Uh, Master..."

Your brother's cock erupts while she's still talking, splattering cum across her face. Maybe half of it lands in her mouth, while the rest drips down towards her chin.

The moment she realizes what's happening, her frown disappears and is replaced by an excited, almost frantic expression. She places her tongue on the underside of Cassidy's shaft, coaxing the last few drops of seed into her mouth.

"Good girl... Good slut," your brother moans, slapping his meat against Mom's cheek a few times before glancing up. "Oh, hey Marcy-Marc."

"Yo," you reply, rolling your eyes.

Noticing that Cassidy just fed your mother a substantial amount of medicine, you grab the silk doily/throw blanket/thingy from the back of Dad's favorite armchair. Then you walk over to Mom and help her up from the floor... And as you do you wipe the cloth across her face, making sure she doesn't get a chance to lick up the rest of your brother's cum.

"Thanks Baby," she mutters, completely missing the fact that you just stole a couple of I.Q. points that were within her reach. She even takes the cloth and continues cleaning up, wiping some stray droplets off of her perky breasts.

You step back and take a moment to appreciate her new-and-improved form. She looks completely different from the woman who raised you, and who lived here a year ago. Her whole body has slimmed down, with the exception of her breasts and ass. Those are actually a bit bigger, courtesy of some top-of-the-line implants. Her face has had some minor work done as well, and the transformation is truly completed by the details: plumped-up lips, blonde hair, and a healthy amount of makeup.

You're getting hard just looking at her. Dad and Cassidy have already busted a nut (or busted a nothing, in the case of the former)... Now it's your turn.