Lesson learned: When naked (because you just stepped out of the shower or whatever), do not cuddle to your bosom a cat who is clinging to a mouse toy. Because when said cat drops said toy to the floor, he will leap for it, using said bosom as a springboard, and his back claws will tear your nipple off.

Ouch.

(Google is going to make me regret using the word nipple, I just know it.)