With her weapon destroyed, Tsumugi attacks the enemy Gauna with her bare hands and Tsuruuchi attempts to take her down while she is distracted but Nagate interrupts him. Tsumugi is then restrained by the Gauna and Nagate steps in to save her. Upon obtaining authorization from Kunato, Tsumugi unleashes an attack that pierces the Gauna instantly, destroying it. Kobayashi then announces that Tsumugi is actually a Chimera, a Gauna-human hybrid developed inside Sidonia, and discontent with the captain for allowing it, the Immortal Ship Assembly decides that they must intervene. After the battle, thanks to Kunato's efforts, all of Ochiai's research is extracted from the auxiliary brain and Kobayashi decides that only she must have direct access to it. Some time later, Kunato holds a meeting to introduce Tsumugi to the public. Upon seeing Nagate, Tsumugi thanks him for helping her, but gets too excited to the point of shaking up the entire room and scaring the audience who turns against her, forcing Kunato to end the meeting. On a later occasion, Nagate and Izana pay a visit to Tsumugi and they become friends with her. Meanwhile, the Immortal Ship Assembly decides unanimously to impeach Kobayashi and have her replaced, but Ochiai appears before them and revealing that he had listened all their conversation, kills all of them under Kobayashi's orders.