There is something deliciously erotic about a Villainess capturing a Heroine.

After all, a Villainess would know those feminine weaknesses...and would doubtless regard her new captive as a lovely doll to play with.

If I were a superheroine, I'd be more frightened of a powerful woman capturing me than a man.

A Mistress, after all, is not bound by any notions of chivalry or gentlemanly behaviour...she can do whatever she pleases with her captive girl!