He's an Animal! (Sans)

... Sans. Wearing his hoodie...?
"Sans, why are you wearing your hoodie?! It's way too hot!"
You went over to take it off and he... Hissed?!
"Sans...?"
He closed the door and sat on the couch, tugging on the hoodie tighter.
"Sans? Are you okay? What did the potion do?"
"... Uh..."
He slowly removed his hood and two little kitty ears popped up.
"Wh-"
A tail began to wave around in the air.
"Sans, what in the world happened...?"
You walked over and sat next to him, rubbing the ears gently.
He purred and nuzzled your hand, a small blush forming on his face.
"Awww..."
You began to scratch his belly and couldn't help but squeal when he began to purr.
"(Name)... Hah..."
You couldn't help but blush when he made such cute noises.
You decided to indulge in this a bit...
"Awww, who's a good little kitty~?"
"Uuuggghhhhh..."
He covered his face in embarrassment.
"Please say it Sans! Oh, it would be so cuuuuuute!"
"But... I'm not supposed to be cute..."
"Yes you are! Your my cute little kitty cat~!"
"Um... I'm... A good little kitty..."
You could barely hear him, which made it even cuter.
You tickled him behind his ears and smiled as his back arched at the sensations.
"Ah...."
You reached for the base of his tail, but just then...
"Woah, kiddo!"
The magic wore off.
You had just groped him.
What.
"Ahhhhh! I'm so sorry Sans I just wanted to pet your little tail and oops was that your spine? My bad..."
"It's okay, calm down. That... Felt really good."
"Uh... Me groping your spine, or the cat thing?"
"I was referring to the cat thing, but... Both."
"Um... Anyway, you were really cute just now..."
"... Thanks. But, uh, can we just forget this happened-"
"Not a chance."
"Awww..."