Over grooming??

Hello everyone!

Its been a little while since ive been on here, but my little Bunny Casper is getting overgroomed by my other rabbit from what i can tell. She is always grooming him and recently has started to make sores on his back, they are generally not big only about the size of your little finger nail but are fresh everytime i find them. I have had him to the vets incase of Flystrike and the likes but they gave him a clean bill of health other than these sores, they gave me Fuciderm to put on the sores which does help, but this does not stop the grooming. Has anyone experinced this before and what can i do to help Casper. Also when i watch them and even when i check him over he appears to strech out when i or other rabbit fuss round his lower back like he is itchy almost. But Mites have been ruled out. Any help or advice would be great. I can get pictures if this would help.

Thanks
Louise and Casper