Well Tameem and Ninja theory has said many times Dante will be a punk. And in Famitsu scan or something he is to be portrayed like a punk from eastern london.
So wouldn't it make sense that punk Dante hangs out with punk girl?
I think you're lookin' way too much into this 'punk' thing. Even if they're punk, I wonder what difference it'd make?
This girl will still be of importance (as pointed out by Wallenb) even if she's a punk.