I don't think this would be offensive at all, it's not insulting people or anything. The weirdest I've seen... probably yours, or Milkycheese2. That name was totally random, and I've never seen a name of just underscores before.
i still dont see that this is being very offensive.
most people dont care about having weird usernames, and they picked it because it is weird. If someone does end up getting offended we can apologize or whatever needs to be done.
Look if it turns into a fight, i'll personally ask for it to be shut don. But so far the only ones make this a fight are the ones that are complaining about a fight starting.
keep to the topic and if it gets out of hand then we can worry about it.