Platinum the Trinity

Platinum the Trinity is a girl who has three souls, including the spirit of one of the Six Heroes. The name of the three souls are Luna, Sena, and Trinity Glassfield. Luna is a rude young girl; Sena is a polite young boy; and Trinity is the spirit of one of the Six Heroes. Trinity's personality is locked within her Nox Nyctores, and she is only able to come to the surface for brief periods of time.

(Source: Blazeblue Wikia)