A male who says to two or more different girls that he wants to be with them both, as he knows that this will give him the most power, control and attention and make him suffer the least pain whilst the girls involved suffer the most possible. In the words of shaggy: "if you want to be a player you gotta know how to play" and many guys aren't clever enough to be a successful arms dealer.
I heard that Aaron's a bit of an arms dealer, but both the girls went and caught him at it and humiliated him. That's karma i suppose.
A gun dealer, Arm means "gun" as in "the right to bear arms" commenly used in Fall Out Boys "This aint a scene its an arms race"
Yo man you got some guns?
What do you think i am? An arms dealer?