A royal swirly is a bullying action in which a person shits in a toilet and dunks someone else's head in. The person is then punched in the stomach by the swirler, hoping the victim opens their mouth out of surprise and sucks in shit. The toilet is then flushed as shit swirls around the victim's head.
1. Earnest is blond, but his hair was brown after a royal swirly.
2. Leonard loves to give the scrawny nerd royal swirlies after class.