Now, this cursed item would is truly quite horrible to encounter. What appears to be a clown costume, worn by a desperate father trying to impress his son on his birthday, actually turns out to be the hair and skin of an ancient demon. Because of course it is.
Wearing the suit means that the creature becomes one with its wearer, fusing all parts of its outfit into one's own skin as two become one. The only way to stop it is to consume five children, or get decapitated, neither of which is particularly appealing.
Clown plays out as the devolution of dad Kent as the costume takes over his mind and body, transforming his blood to rainbows and rendering suicide impossible. The contrast between no-one else taking him seriously in his outfit and his hunger for flesh is a chilling one - and a warning to not put anything you find in someone's old basement on your face. If it's not got people germs, it's got a sadistic demon living in it.