Guess he's not a fan...

Is there any way you can shield him from the wind it makes? Or is it the sound that the bunny doesn't like?

Tastes like chicken...

Elmer Fudd, at your service! He’s got a great recipe for Hasenpfeffer! Or you could get Glenn Close to take care of Thumper. She won’t be ignored, Dan!

I'd he making rabbit stew lmao

I'm the same way. I need some kind of background noise. I also live in a old house with creeks and what not. If I dont have a fan I'll just sit there anticipating the next random noise. My cat hated my fan at first. Wouldnt sleep in my room. Which is a bummer because I like my little cuddly fur buddy. After once the summer rolled around he realized it would cool him off. Now winter or summer. If the fan doesn't point to his favorite corner of the bed he gets cranky. Maybe the same could happen with your friend.

You should still have a separate bathroom right? Just put him in there

So, heres what you do... Re-home the bunny. Problem solved.

Put up a sheet in front of his cage between him and the fan. Or move the fan closer to you and further from him. I've kept rabbits for 25+ years and I am used to dealing with them throwing a bunny fit!

You have the fan on only at night? You could try to train him to ignore it by turning the fan on every day for some time, preferably until he stops thumping. Then give him a treat. I don't have bunnies so I don't know if they can be trained like that, but my friend has some and they seem clever.