Troidal operates as second-in-command of the criminal syndicate Id, a bioroid manifesting as a young man. Initially following Megadeth's orders, he executes attacks against the Zaizen Group and its heir, Jun Zaizen. Upon learning his artificial origins directly from Megadeth—specifically his creation by Jun Zaizen—Troidal experiences a fundamental transformation. This revelation ignites a fierce drive for vengeance against humanity.

Convinced of bioroid superiority, Troidal establishes the breakaway faction Neo Id, dedicated to purifying the world by eradicating humankind. He reprograms Crola, an emotionless female android originally built by Jun Zaizen, to join Neo Id. Over time, Crola develops affection for Troidal. After Megadeth's defeat, Troidal ascends to full command of Neo Id.

Troidal escalates his campaign by orchestrating Jun Zaizen's brainwashing in Episode 28, installing him as Neo Id's figurehead leader to advance the anti-human agenda. Troidal possesses a documented vulnerability, experiencing an allergic reaction to crabs. His core narrative revolves around existential resentment over his artificial creation, fueling a vengeful quest that positions him as a primary antagonist committed to the systemic annihilation of human society.