You flaming bet you could light your own
Cigarette with ya asshole
Referencing the “Liar Liar Pants on fire” chant that little kids say. They are lying about banging so hard that they could light a cigarette with their assholes.
A homosexual can -in slang terms_ be referred to as “flaming”. Royce is saying that your asshole is so “flaming” that it could light a cigarette. Which ties to his unicorn description previously, since homosexuals and unicorns have a connotation.
You can also notice a bit of wordplay in the fact that the term “fag” is both a British colloquialism for cigarette and an American slur for homosexual.
A second wordplay would be on the fact that gay men have sex through the anus, therefore it being so hot from the recent intercourse that they can light a cigarette with their own buttholes.
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