Six serves the Penguin Empire until exposure to HI-ERo particles from Rikantz Seaberry (Ritz) radically alters him. The particles trigger a transformation into human form and induce complete amnesia, erasing his memories and original identity. In this state, he meets Kyouko Sonan; as they walk and talk, they form an unexpected connection and develop a rapport.

Upon regaining his memories, Six reverts to his mission and attempts to capture Kyouko. This leads to a confrontation involving Daimidaler units where he sustains fatal injuries. His final words express a desire to Kyouko to have been her partner, revealing unresolved conflict. Though seemingly deceased, Six reappears in his original penguin form during a post-credits funeral scene, hiding behind a pillar. He intends to announce his survival but misses the chance to reveal himself.

Later, Six plays a pivotal role by successfully reversing the penguin transformation inflicted on Shouma Ameku by the Penguin Empire, restoring Shouma to human form and facilitating his return to Kiriko Kiyuna. The character is occasionally mistakenly referred to as "Sex," stemming from a mispronunciation or misunderstanding of his name.