It's a commission.
Having 6 arms do help a lot when you're a gunfighter. I do think she's pretty badass that way 
She's using three Smith&Wesson M39 (though only 2 are shown on pic) and three Grand Power K100 MK7. That doesn't mean I'm a fan of firearms, since I've never even hold any in my life.
Anyway, that's the kind of girl I wouldn't piss off, hehe