2 days ago I finally brought in a stray that I've been feeding for about a year. He's been holding up well in my bedroom, not clawing the door to get out...not even meowing...I have one big issue though. He poops and pees on my bed! I've been about out of my mind these last few days.. finding out he has FIV, deciding to keep him and now this. I've been cleaning my mattress, carpets and washing my sheets several times a day. Last night out of desperation I cut and taped 6 trash bags to my mattress. I've never had an issue like this I have 3 other cats..2 were also strays and they took right to the litter box. Tonight I actually moved my bed into the living room and put plastic on a large area of the bedroom floor only to have found him peeing on the side of it. I've provided a very small litter box with small amounts of litter with some dirt and gravel mixed in. Also have a rubber maid tub without lid that is cut so he can walk into it. I've now moved out of my room and I'm at lost for what to do. I keep trying to put him inside the box.. But he jumps out. I've put droppings in the boxes with no luck. He's neutered and the vet thinks around a year old. He has had diarrhea since before I brought him inside and received a antibiotic shot from the vet a few days ago.