Person B, the main villain, being supposedly vanquished (thrown into lava, fatally wounded, blown up) by the primary hero group. Person A, a member of the hero group, rescues B and secretly nurses them back to health. What sort of problems does this cause?
Harmony Saves Brannigan AU
http://otpdisaster.tumblr.com/post/124453662565/person-b-the-main-villain-being-supposedly
Harmony Saves Brannigan AU! I demand it.