Drakengard

Drakengard/Drag-On Dragoon is a videogame series directed by Taro Yoko and created by cavia. It takes place in a real shithole of a fantasy world where everyone is trying to kill everyone else. If they do manage to kill everyone else, then monsters from Beyond will come in and kill who remains, and if they don't then the dragons will do it for them.

In the first game the player plays as Caim, a Non-Hero of the highest degree of Non. After his sister professes her love for him (yes, in that way) and he absolutely turns her down, she kills herself. Unfortunately she was the Seal which kept monsters from Beyond from invading, so monsters from Beyond invade. In one of the endings the poor schmuck who was in love with Furiae tries to bring her back to life with an Egg of Resurrection that the monsters from beyond brought with them. This, of course, turns her into a winged hell-demon. After just barely managing to destroy her, Caim rests on top of a destroyed skyscraper and witnesses every other egg also hatching into a demon Furiae, dooming the world to destruction.