It's just okay. I get what the author was trying to do with the whole "it's not rape because its necessary " and the "hes not cold, its his medicine " thing but in the begging there really are no hints which is what's frustrating. Usually there is a small blush here or a cute look there but there wasn't really anything before the big reveal. They even claimed that he was taking regular medication but you never see him take the medicine and just hear about it during the big reveal. Overall, this manga should have been great with its premise but instead it was just okay.
Ookami he no Yomeiri