Using art of someone’s personal OC for your rp character is 99% of the time not the compliment you think it is.
My ocs are first and foremost for me, and are far more personal things to me than just a thing I draw for other people to look at, and seeing them repurposed in ways I did not intend them to be used kinda sucks. Telling someone you’re gonna use their creation for your own reasons and expecting them to be happy about it when you didn’t even ask also sucks.
If you’re a creator who doesn’t mind people doing this, then that’s great, but I’m not cool with it.