Yes, Loras had been naked in Renly's expensive sheets and on his couch and even in the kitchen as well as other random places in the house, so it wasn't a big deal to him. Not when the sudden appearance of his crown was what was important here.
As Loras took his hand and guided to towards his mouth, Renly leaned down a little until his chin rested on Loras' shoulder and they were both staring at the crown at about the same level, "It's ironic. Around Christmas, Portia and I joked around about her getting me to wear one of those antler headband things." Honestly. what were the odds that his crown would be all antlers?