Sudden aversion to being touched on right side

by Sarah

Hi everyone.
My rabbit's been reacting very strangely lately. Normally he is fine with me touching and letting him but recently whenever I touch a certain spot on his right side, he will turn his head and try to lick it/clean it.

It's not a place he can easily reach by simply turning his head so he ends up going in circles trying to reach that spot (picture a dog trying to chase its tail). I find this behavior really odd and I'm not sure what could be wrong.

It seems to me that its only that one spot which is affected. It looks fine to me but its hard for me to get a closer look because as soon as I know touch it he starts moving.

Any help with what this is please or how I can get him to stop turning do I can get a better look?