@Randrak42
Because then the whole joke is lost (logic).
You come up with a crazy world where everything is possible.
But they also have internal logic.
You can cut via swords the ships and the like. Look at the logic - why 7 swords? Because 7 is greater than 4. And everyone says MC can not win - he has only two arms and legs.
Of course this is not hentai - so we're talking about the arms and legs.
But the author comes up with a very funny turn - at MC have teeth - the teeth a lot.
Turn teeth into swords, and the outcome of the battle resolved.