One theory states that Ryomen-sukuna is a symbol of twins and brothers, therefore it refers to Oousu no Mikoto and Ousu no Mikoto (i.e. Yamato Takeru no Mikoto and his brother), twins in ancient Japanese history.
一説では両面宿儺は双生児や兄弟の象徴であり、古代史での双生児、大碓命小碓命（つまり日本尊命とその兄）のことという。