'Feel Free to Be Irreverant' perhaps?

I swear I saw "weird comments welcome" once, but that might still invite creepiness...

"Creepy messages welcome" just sounds like you want people going "Yeah I wanna bend them over the counter and chucklefuck them until they spew confetti" or something like that on every picture of a relatively attractive character (or person). From what I've seen it more or less just invites the sexual weird comments that a lot of people dislike, since it'd be seen as kinda-to-very creepy to just comment them under random drawings or photos.

Hope your headache goes away soon!

Comment at will.

what if im feeling nefarious

then be so, it'll be funny

seasoned curlies

dropping a brick on your skull.

70MIL damage

100 Degree Damage