Sky Master rules Synapse, the advanced realm that creates Angeloids, wielding absolute authority over its operations and inhabitants, including those deployed to Earth. As seen in "The Angeloid of Clockwork," Sky Master directly intervenes in the fate of Hiyori Kazane. After dying in an accident, Sky Master erases Hiyori's existence from human memory, reactivates her stored consciousness within Synapse, transforms her into a powerful Angeloid, and commands her to eliminate Tomoki Sakurai and his allied Angeloids. Sky Master activates Hiyori's self-destruct collar when her mission fails.

This figure demonstrates the power to manipulate memories across both Synapse and Earth and wields control over Angeloid functionality, imposing obedience protocols and triggering self-destruct sequences. While not physically detailed in the series, Sky Master's influence persists through proxies like Daedalus and Synapse's governing systems. Motivations center on maintaining Synapse's dominance and suppressing threats to its authority, particularly from Tomoki and his allies challenging Angeloid subjugation.

Tomoki's final wish triggers a universal reset that disrupts Sky Master's control over Synapse and the Angeloids, restoring destroyed characters and altering the established hierarchy. Sky Master's origins, personal history, or specific identity beyond the title "Master of the Synapse" remain undefined. The character reappears in "Eternal My Master" where the consequences of Synapse's destabilized power structure unfold, though direct involvement is not detailed. Sky Master functions primarily as an overarching antagonist representing institutionalized control.