I think they pee on beds/couches to prove a point- “This is mine now- I like it, therefore you are no longer worthy of it so I shall decorate it to prove my point.” BunBun has peed on the couch when I used to discourage him from ripping apart the cushions. He also peed on our bed several times- I think this is because he’s not allowed in our bedroom all the time, just when we’re there. Once he peed on my pillow when he was there alone with Rick
. I’m sure if he had free access to the bedroom/bed, he wouldn’t pee on it because he would be secure in the fact that it was “his”.
I agree- the simplest solution is to only let him have supervised visits to your room. Be prepared for him to try desparately (and deviously) to sneak into your room though. When BunBun used to play on our bed, he was always trying to break into our bedroom. We would open the door and immediately a twitchy little bunny snout would pop into the room- if we weren’t quick enough, he would dash under the bed and hide. He would also lurk in the hallway and listen carefully for the door- if Rick forgot to fully close it, he would race down the hallway and try to squeeze in. I lived in fear of carelessly swinging the door shut and crushing his poor nose. We finally had to altogether stop letting BunBun into our room. It took a few weeks, but eventually he gave up on it. Good luck
.