I honestly just threw up a little. I really have to stop reading FML on a full stomach.

So he thought he was getting pussy instead?

What does his cat do to him? And visa-versa.

I don't want to be one of those WUT THIS ISNT AN FML chumps but I really don't see the problem here. You said it was your first time doing that to your biff so it's not something he's come to expect. He was rightfully shocked and freaked out when he thought his cat decided to lick his genitalz. He realized it was you and asked you to continue. What exactly is the issue? :P

How close is he to his cat?

So, do you have a sandpaper tongue? Ask your doctor if they make something like Chap-Stick for rough, chapped tongues.

Oh I can see so many bad jokes coming it hurts ._. But on a more serious note, my cat has the habit of waking my boyfriend up by walking his legs up, continuing to his torso, meowing at his face, then walking down and up his body until he puts him down or gets up, so seeing as op boyfriend hasn't gotten any action lately (I suposse?) he could've easily mistaken "something repeatedly touching" his body for his cat in case his has a similar habit since you can't really distinguish what kind of "touch" it is until you're fully awake. You sometimes even see images from your dreams for a couple of minutes.

He's getting pussy either way. It's a win-win for him.

did you continue..?.-.

Me-wow.