I think the pink haired dude knows MC before he was Amon consort, I think Amon took fancy of MC 500 years ago when he saw him playing that harp, and someway he is brainwhasing him with those things from the ritual, is just a theory, i haven't read the novel
So i read the next 3 chapters, and the reason he's being so cold in this moment is because now he knows what happened to MC, and he is disgusted with his past self thinking that MC saw him like one those rapists, but they will talk in the next chapters so don't worry
I think the pink haired dude knows MC before he was Amon consort, I think Amon took fancy of MC 500 years ago when he saw him playing that harp, and someway he is brainwhasing him with those things from the ritual, is just a theory, i haven't read the novel