|Ministry of Magic Classification||
A Red Cap, also known as a Porter Demon is a Dark creature found in dark, damp locations where blood had been shed, such as dungeons or in deserted battlefields. They carried thick clubs with which they bludgeoned those who got lost.
Red Caps can rather easily be repelled with simple charms and hexes, but are extremely dangerous to solitary Muggles and on dark nights will attempt to bludgeon those passing.
Professor Remus Lupin taught his third-year Defence Against the Dark Arts class about these creatures, which were later covered in the final exam. Red Caps are covered in The Dark Forces: A Guide to Self-Protection by Professor Quentin Trimble, as well as Fantastic Beasts and Where to Find Them by Newton Scamander.