Can someone help me figure out the title of this anime. It started out with a girl transferring her own blood to this young boy. I can't remember much because I was young when I watched it. But I remember the girl was a pilot of a robot, probably a gundam?. I'm not sure but the young boy became a pilot as well. Its probably a mecha series but I'm not sure. Please help me figure it out. Its killing me. TIA