Astrid is a member of the Royal Family of the planet Tatra and the only daughter of Grand Empress Ananke.

Astrid is steadfast and bold, caring a great deal for the welfare of others; this has lead her into conflicts her mother believes she ought not be involved in. She initially left Tatra in pursuit of the Archdemon Antistrophe, who had committed atrocities against her people deemed unforgivable. This eventually lead her to Earth, accompanied by her bodyguard, Arietta, and her friend Liedryyn. Ananke also tasked her daughter with a top secret mission which she was forbidden to reveal even to her comrades. Her arrival was surveilled by EXOSPHERE, who thusly named her Emergent 3317.

Though slightly wary of humans, Astrid shows a willing kindness to those who deserve it. She is a gifted pilot and posesses extraordinary skill with the legendary petalglass blade, Astradea, which was bequeathed to her by her mother before her new journey away from Tatra began; it answers only to her and can fly across vast distances to her location by her will.