Yuuto has been taking care of his step-sister Kaori since the passing of both of their parents. Their life is hard, but they are happy together, at least until the day they are transported to a parallel world that they will later call Phantasmagoria... In this world where he can't even understand a single spoken word; his sister is taken prisoner and her captors, calling him the 'Etranger', force him to fight wielding a sword that tries to control him instead... Enjoy!