It isn't anywhere in the rules, old boy - a fact which you are obviously well aware of. Else you wouldn't have asked it. A touch of Socratic Irony, there?
However, the forum's name is pretty plain - fanfiction. Constructive criticism thereof. In addition to that, there's fapping, there's lively discussion, there's some trolling and everyone tends to have a good time.
If I wanted a VS board, I'd go and surf GameFAQS. If I wanted juvenile insults and a thin veneer of intellectualism, I'd go to StarDestroyer and weep as nerds take their faggot tree too seriously.
Most annoying of all? We've actually managed to keep the Naruto VS topics civil, for the most part, while staying on-topic and coming up with outcomes that seem plausible. But here? No such luck.