Beta

Beta (베타) is one of Sophia Amae 's "child", and Horyang 's and Cassano 's "brother". He is possibly a living ignition weapon. As well, before he left Horyang and Cassano, he explained that he doesn't find interest in "halfies," which can possibly mean that Beta, unlike Horyang and Cassano who hold halves of their Demon, may be an ignition weapon that carries the powers of an entire whole Demon.

Appearance and Personality
It's a not very tall boy wearing a blue hooded jacket. He's got bandages that cover his eyes and hair. We can see underneath blue shiny veins that covers his body. He is moving around with a dropper, which gives him constant perfusion of some chemicals, we do not know as for now if those are part of the transformation process in living ignition weapon or if it provides medication for any side effects it may induce.

According to Sophia, he has a lonely and suspicious personality and has always lived in the laboratory. His statement on his  "brothers" as being "halvies" may hint that he has a complete "demon" inside of him.