Ok so DH and I have separate towels. I keep his on the towel rack and mine behind the door on the radiator.
I have told him numerous times that this is the towel status quo.
I've lost count of the amount of times I've gone to have a shower to find that he's used MY towel. I know when he has as he's a lazy beggar who leaves it on the floor soaking wet.
I have asked him to please stop using my towel. This didn't work, so I took to taking my towel out of the bathroom and leaving it somewhere else.
EVERY SINGLE TIME I forget to do this and leave it in the bathroom he uses it!!! 
It's not like it's easier to get to; he has to reach past the laundy basket and behind the door to get to it!
AIBU to kill him now think he's doing it purposely to wind me up?