What's this anime?!?!?!?

All i can remember it was about this school who summon these spirits with music and the two main characters, one was a male who was an Amazing singer but used an keyboard instead and the other i think was a red haired girl who was a Spirit who he sang to on a full moon and they make a contract or something like that. I can remember there was some romance and the Spirit girl was a bossy type who the male kind of obeyed like in torodora hope this help and please answer x