It is a long story, but I will give you the short version. Two years ago a group of magi held a war for the right to claim the Holy Grail and the right to make a single wish. They decide the winner by summoning ancient heroes and having them fight to the death, I was one of those heroes.

After the war's end I was able to say in the modern age by making a contract with the woman I now call my wife. If something were to happen to her, I would return whence I came.