To be incredibly epic at basically everything. Seems to be from a different dimension, though this is up for debate. Will not admit to having ninja skills even though said skills are witnessed regularly. Prone to anime-type reactions (aka loud and obvious), usually ending in some form of destruction.
Person 1: WTF happened in here!? All the desks and chairs are destroyed!!
Person 2: Someone pissed off (insert random name here).
Person: What an idiot, everyone knows (insert random name again) is a Sei.