Heh, tough choice. I'm giving this one to Selphie, because whenever Tifa hits her a lot, Selphie will get a limit and can cast Full-Cure on herself. Or even cast a series of those Black Magic spells at Tifa. Or even cast The End on her if she's lucky.

Ms. Lockheart at least gets credits for putting up one hell of a fight against Ms. Tilmitt.