I think it’s pretty typical for bunnies to be “obsessive” about something for a period of time, then move on to something else. A lot of bunnies like to have projects to work on, so they decide somehow that one specific thing will be their project, and become obsessed with going back to that place and working on it. As long as it’s not destructive and you don’t mind, let him have at it! Otherwise, just try to keep him away and give him other things to do and with time he’ll probably find a new project to become obsessed with.

My bunny does this on ‘his’ bed with ‘his’ blanket so you could provide a setup like that and see if he likes that too…

Just buy one of those round donut bed type things and put a towel or small blanket on it… he’ll probably dig that too

I think Elrohwen put it well. Bunnies are cute because they really are totally neurotic, and once they get a spot, activity, behavior or particular thing in their head they come back to it over and over and over and over and over….It’s true they like projects. Usually they have to get bored of it on their own before they can move on to a new one. Burrowing in blankies is triggering their burrowing underground instincts. They sometimes might even think they are providing for the family by being a really good digger. So they want to complete their project. Especially if it’s wicked fun.

As long as you use a mild vinegar and water spray to get out any scent of former pee in that area, I’d say you’re fine to let him do it.
It’s better if you take pictures, though.

Eddie used to do this with me. On my blankets. ON ME. Drove me freaking nuts cause I’d let him go for a few minutes then put him on the floor and he’d just come back. And I even tried laying on old sheets and then giving it to him thinking it was my scent he was after. Oh heck no, would completely ignore the sheet and come back to me and my blankets. I couldn’t really ever get him to stop. He’d have periods where he wouldn’t do it as much, but then would always come back. Then I got Lollipop and that redirected his attention cause there was an icky, gross GIRL in the apartment. lol

So I guess I have no advice other than sometimes you just have to ride it out like others have said. They are truly the most stubborn animals sometimes about things and you either get frustrated and keep fighting or you just give up and give in. lol

Yup Blu is guilty of this too. His current “project” that he works on a few times a day, is digging at his grass mat … he gets in squatting/digging stance and goes crazy digging at the corner of it..and simultaneously chewing on it. he used to do this in his cuddle cup when he was a baby. It started out of the blue (no pun intended…) and one day I noticed his grass mats were slowly disappearing. Funny because he’s had them forever and just started digging/eating them. It’s cute bc I think he really believes he’s doing something very important but if he does it at just the right moment (i.e. I’m a little stressed out, etc.) he will drive me NUTS because of the scratching noise on the wood floors!