What could cialis do for a girl?

Nothing . . .: At least nothing proven yet. Cialis (tadalafil) & its competitors work by increasing blood flow. In the penis, more blood means an erection (assuming no venous leak). In the lungs, this helps those w/pulmonary arterial hypertension ie Revatio (http://www.drugs.com/revatio.html) aka Viagra (sildenafil). But so far, FDA has not approved Cialis for female sexual dysfunction.