If you want a serious explanation as to what happened happened, here you go.
Spoilers for those that have not watched the latest episode of Guilty Crown
1. It was to give Shu motivation to go kick ass. As we're likely nearing the end of the series, something needs to jump start this whole thing, so unfortunately, a sacrifice is needed.
2. To resolve the love Triangle. Let's be honest, with the way this series was going, it was going to end badly.
3. To make Ayase a viable love interest. While subtle, it's there, but unless something happens to Inori, I doubt it.
4. Her void is a Game Breaker. Seriously, unless it's a fatal wound from the word go, anybody can be effectively immortal, and where's the drama in that?
But if it makes you feel any better, you can blame one person for all of this. Treacherous Traitor Yahiro.
(Wouldn't it be Souta?)
Souta is an idiot, but wouldn't have done something this stupid if it wasn't for Racist Yahiro.
