They didn't give him aphrodisiac, they were treating his wound that was caused by the rough sex
Yes, they did try to treat him, but chapter 4 page 13 was kind of weird, Minori is feeling hot and somehow horny. So I suspected that the other guys probably put some
aphrodisiac in Minori's medicine.
It's just a guess tho... ╮(￣▽￣)╭
Yeah that part's kinda weird, but after Minori took the sleeping drugs and medicines, he'd always sleep for days before waking up, so I don't think that the aphrodisiac, if there were one, would still work
I still hate the idea for Youkou to raped Minori and for the others to give him sleeping drugs and aphrodisiac u know -_-