Seraph of the End Maybe? It's nice.
And yeah, I rewatched Guilty Crown for like 4 times and never get bored of it. The story is so touching tho specially..
At the time when Inori declare that she'll always by Shu side whatever the situation if, Even if the whole world hate him, she'll always stay by his side.
Just like the song
The Ost(s) is nice too.