Rectum, I'm like a chromosome I always X them
The genetic basis for sex determination is in the X and Y chromosomes. Dudes are XY and girls are XX. But in either case you have at least one X chromosome so are always “Xed” just as he does with his opponents.
“Rectum” is continuation from the line before, but also a pun on “recked them/recked ‘em.” This just lends weight to the fact that he always “X'es” his opponents.
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