I see your point breh...but fukk this logic. Do you know how hard it is to find someone you really love that loves you back? That shyt ain't easy fam. So if you find it, whatever the circumstances (assuming she ain't a criminal or nothing or vagabond), then you gotta take it.
shes 21 , he's 20, its not love its lust.
he's only been messing with her for 3 months, he's just the only "good dude" out there that will be with her and her seed