Mochikuni Akai is a senior pilot in the Knights of Sidonia and the leader of the Akai squad, designated as unit 001. He is noted for being the youngest Gravity Cup winner in Sidonia's history and for retaining that title for thirteen consecutive cups, a testament to his exceptional skill as a Garde pilot. Despite his status as one of the ship's most successful pilots, Akai is portrayed as laid-back and friendly, and he behaves cordially toward Nagate Tanikaze. His role in the story is brief but impactful; he and his entire squadron are annihilated after engaging Gauna 487, an early conflict that highlights the lethal threat the Gauna pose. Akai's motivations are rooted in his sense of duty to protect Sidonia and his commitment to his squad. Key relationships include his command of Akai squad and his respectful interactions with Tanikaze. His character development is limited by his early death, but he is remembered as a pilot of extraordinary ability and a leader who served with distinction.