It was one of those cases where I came up with the name as a ten or so year old and it just stuck.
I forget where I heard of it first, but it means "one who leads others, especially in revolutionary or illegal activities."
Lots of people confuse it with Ringmaster, the leader of a circus. Googling Ringleader even brings up Circus costumes...
The 7's come from a mixture of needing a number when I got a Ps4 and the fact that I forgot that my favorite character in a series was #8 not #7...again, early childhood mistake lol