Roses are red, Violets are blue... I fucked your mother's ass, and she had you.
Roses are red, violets are blue
Explanation
Explain Bear
Listen here, genius. The joke's saying roses are red, violets are blue, and then WHAM! A vulgar reveal about the listener's mom... You know, the woman who birthed you? Considering your understanding of jokes, that might be the only thing she's good at.