Seven

A highly skilled mercenary, Seven carries a strict, no-nonsense attitude. She is trained to stop threats at their tracks when any hint of danger is suspected.

Details on Seven tends to be unknown - in fact, their real name isn't even Seven. They are a very private person, being highly reluctant to participate in social outings or even simple conversation. Although, if you ask anyone who's known Seven for a long time what her deal is, they may mention that she wasn't always like this...