Basic Trope: The hero does something good, only to be "rewarded" with suffering.
Straight: Marcy rescues a Damsel in Distress from a monster. Unfortunately, this grabs the attention of the monster's master, who decides to punish her for her defiance...
Marcy rescues a Damsel in Distress and escorts her home... only to learn that the village was trying to sacrifice her to protect themselves, and they aren't too pleased with her interference. She's attacked and arrested, and they plan to sacrifice her instead. Before they get the chance, however, the monster attacks first — along with his master, looking for the one who defied him.
Jim gives a homeless man a sandwich to eat. The homeless man eagerly accepts the sandwich, but has a severe allergic reaction to it and dies. The homeless man's brother, having recently heard of his poverty, comes to pick him up, only to find him dead at Jim's feet. Jim is arrested and sent to jail for life due to "killing" the homeless man.
Marcy kills off many innocent people just For the Evulz, yet the mayor rewards her for her monstrous deed.
Subverted: Marcy is in turn rescued from the monster's master by the damsel she saved earlier.
Double Subverted: Although Marcy is rescued from the monster's master by the damsel, it turns out the damsel was just saving Marcy so she - actually a vampire - could drink Marcy's blood.
Parodied: Marcy finds a little girl wandering around lost, tries to help her find her parents, and is promptly accused of trying to kidnap her and run out of town.
Zig Zagged: Marcy is captured by the monster's master, and rescued by the damsel. It turns out the damsel is a vampire who plans to drink Marcy's blood - but this is only because she's grateful, and wants to give Marcy vampiric powers to assist in her fight against evil. After Marcy convinces her that this isn't what she wants, she joins up with Marcy, and the two defeat the evil master together. However, this draws the attention of The Man Behind the Man...
Averted: Marcy rescues a Distressed Damsel from a monster. She is given a reward by the damsel's thankful father, and sets off to perform more heroism.