The first child, Hiren believed himself to be the true heir of the Arsala'an legacy. When he realized that Ai had given Takaa the Chimera Flame instead, he grew jealous. Tsukiko used that to her advantage and controlled his mind. When the children were travelling, Tsukiko triggered his rage and Hiren attacked Takaa. The two fought. Shino interfered, but that did not stop Hiren as he killed him without hesitation. As he was defeated and slain by Takaa, he came to. In his last breaths, he could only ask "What...happened?"
Hiren spent the longest time with Kirita and Ai and felt the closest to them. He fights with the Elder Strength Fist, based of Goju Ryu, like his father.