How Accurate Is This Statement

So I'm reading this novel right and one of the characters Aaron has sex with his girlfriend for the first time later on his friend Craig asks how it felt and Aaron says it feels like the inside of your cheek I'm just curious as to the accuracy

 

What is the title of the book you're reading?

 

It's Kind of a Funny Story by Ned Vizzini

 

Are you asking if the inside of pussy feels like the inside of your mouth? My inside cheek is a little rough, I smoke. I guess that's an ok analogy, probably more like the inside of your ass!