Psygate is a Sistarian alien psychic energy being who, with her sister, Selgate, crash landed on Earth. Near death, G.U.A.R.D.'s Astroguardians arrived at their crash site and nursed the energy beings back to health. Gracious for the kindness provided and amazed at their incredible generosity, sincerity and desire to save them, both Psygate and Selgate decided to aid GUARD and the Terrans for as long as they were needed. Selgate, wanton for stopping the Soltans from further aggression, teamed with the Starfighters in a new android body, while Psygate went on to volunteer assisting GUARD's newly formed PSIGUARD Division.
Psygate initially retained her energy while working in GUARD, however, after several civilian heart attacks and some fearful bouts, Psygate decided to also wear an artificial body like her sister, Selgate.
Once established, she aided GUARD personnel in learning how shield their minds from other intrusive psychics, such to the point that to any average psychics on Earth, it would seem as if all GUARD personnel had been removed from the psychic plane.
Even though intentions were well meant, GUARD desired another division, XGUARD, to monitor the psychic training and blocking to ensure that Psygate (or Selgate) weren't taking over minds rather than helping shield them.
Psygate's intentions are truly honorable and believes GUARD and all Terrans to be highly respectable, regardless of their violent and nonsensical political and religious beliefs. Considering the Terrans to be a parallel in Sistarian evolution, she wants more than anything to ensure the Terrans don't go the way the Sistarians did against the Soltans of abject extinction.