In episode 61 Matt tries and fails to turn Liam into a kitty with polymorph.

What if later on they like, do that in the bedroom, in a manner of speaking. Like Matt has some prop ears lying around and Liam puts them on as a joke and Matt blushes, and one thing leads to another?

Bonus for lots of licking, biting, purring, Liam really getting into it and trapping Matt in bed and hissing when he tries to leave, etc.