Astaris Vega was born to Magnamum Vega, a criminal esper slain by the protagonist in a fatal clash. At five years old, witnessing her father’s death activated dormant psychic powers that accelerated her body to a young adult’s form while her mind remained trapped in childhood. The traumatic metamorphosis purged her memory of the incident, including any awareness of Justy’s involvement in her father’s downfall.

To contain her overwhelming psychic energy—which surpassed conventional esper limits—she wore a suppression headband, echoing the protagonist’s own power-regulation tech. This restraint curbed her abilities to prevent accidental devastation. Though raised by a Cosmo Police guardian as a surrogate sibling within a makeshift family, legal ambiguities classified her as a detainee due to her inherited criminal lineage.

Her fragile equilibrium shattered when rogue espers weaponized her buried trauma through collective telepathy, violently reviving memories of her father’s demise. The psychological assault ignited a feral rage, unleashing cataclysmic destruction on spacecraft systems and a frenzied psychic assault on her guardian. Overwhelmed by the outburst, she collapsed unconscious in the void of space, later rescued and subjected to a memory wipe that restored her childlike psyche.

Distinguished by crimson hair and deep purple eyes, Astaris embodies a paradox—naivety cloaking apocalyptic potential. A mission on Earth briefly intertwined her path with a Japanese schoolgirl’s, though specifics of their interaction remain unrecorded. Her narrative orbits an unending cycle: suppressed memories exploited by foes, eruptions of uncontrollable power, and eventual reset to a fragile, dependent state. Each confrontation concludes with her return to a docile role, emotionally tethered to her guardian, perpetuating a loop of stunted growth amid recurring trauma.