イリウム

The world Irium is a world ruled by magic. One of the most powerful magicians of Irium, the young and lovely Seria, decided to pay a visit to the magic-less world which is our Earth. There, she met a young man; they fell in love, and had a child together. But Seria eventually had to return to Irium. The child, who was named Masaya, grew up on the Earth and turned to be a normal teenager, unaware of the magical powers sealed within him - until a messenger from Irium appears on the Earth and tells him that their world is in great trouble, and he is the only one who can save it...

[From Mobygames]