Baji Keisuke is a childhood friend of Mikey's who started Toman and is the commander of its first division. Baji is first shown to the viewer when Takemichi is taken to Valhalla headquarters by Kazutora. Baji is about to beat up his close friend and vice commander Chifuyu in front of the assembled Valhalla crew to prove his loyalty. Takemichi was previously ordered by Mikey to bring Baji back, as he had apparently betrayed Toman to join Valhalla. Baji refuses to go back to Toman even after Takemichi tries to get him to return. He himself says that his motives are that he hates Toman and never wants to go back to the gang. Even when his closest confidant Chifuyu tries to talk him into it, he does not change his mind. Later, Baji's motives are explained in more detail. (Source: NinskiBobinski)

Aika was Mahiro's sister that was brutally murdered. She had a tendency to quote famous books such as "Hamlet" and "The Tempest" by William Shakespeare. She is based on Ophelia and Sycorax, characters from Shakespeare's plays.