From Valkyrie Scanlations:

The princess of the kingdom of Dipan, Alicia, was abandoned by her parents when she was still a child. The rumour says that she was posessed by a Demon and therefore lost her life. But the truth reveals different. Alicia in truth, inherits the soul of the Battle Maiden Silmeria, one of the three Valkyries, what she has to hide from the rest of the world. That of course gives people reason to think she has a split personality. She is taken to a castle far away from her kingdom and hidden from the public and ever since living a quiet life. Until that one day when Odin, the lord of the gods, decides to come after the lost Valkyrie and forces her to return to Valhalla...