In their Avian disguise, mimicking the Avians of their homeworld. Specific notes being: Percy retains some of their more mammalian features (Teeth, fur instead of feathers at the face and chest. Noticeable ears.) as well as some species traits, like the visible extra 'fingers' making up their wings.
(This is a reupload to the CORRECT account, as VirusNights was an old username I no longer use.. And didn't realize I was on the wrong account until I'd uploaded two pieces lmao. rip.)