A more elaborate explanation of this subject can be found here, on Castlevania.

A Valmanway is a rapier-like sword whose name means "blessed winds." It is a light enough sword that the user can swing it while walking or running. When swung, this weapon creates multiple wind arcs, that can deal as much damage as the blade itself. The arcs, may move with the blade or any other direction away from the user. Each arc has about the same reach as the weapon. This means that the user can get many hits in close combat.