Asteria, whose full name is Asteria Lizamarie De Roschefall, is a character from the anime Lagrange The Flower of Rin-ne. She serves as the acting Chairman of Novumundus, the organization that oversees the Vox units and their pilots. In this capacity, she holds a position of significant authority and is responsible for making strategic decisions regarding the Vox and the defense of Earth.

In terms of appearance, Asteria is depicted as a young girl with blonde hair. Her physical youth contrasts sharply with the immense responsibility she carries, a common characteristic of her role. She has a notable presence, described as having an outsized attitude and a big brain, suggesting she is highly intelligent and self-assured for her age. This intelligence is a core part of her character, as she is able to analyze complex situations and issue commands to those older than herself.

Personality-wise, Asteria is portrayed as being very direct and authoritative. She does not hesitate to exercise her power, as shown when she immediately grounds the main character, Madoka, to prevent her Vox from going on another rampage. This decision showcases her pragmatic and cautious nature, prioritizing investigation and control over reckless action. She interacts primarily with the adult leadership on the base, including Madoka's aunt, with whom she seems to share a particular understanding that eludes the men in the room. This suggests she is adept at navigating political and interpersonal dynamics.

Asteria's role in the story is primarily that of an instigator and an authority figure who reveals more about the world's history and the power structures at play. Her arrival at the Pharos base serves to expand the series' backstory, including details about Earth's status as a neutral territory for twenty thousand years. Her actions, such as forbidding Madoka from piloting the Vox Aura, create direct conflict and tension with the main cast, forcing Madoka's friends Lan and Muginami to rally in protest. Later in the series, her role evolves to include confronting key antagonists. In the second season, she directly confronts Moid, a primary antagonist, who reveals his motives for manipulating events and opening the Rinne. This positions her as a key player in the final stages of the central conflict, moving from an administrative overseer to an active participant in the story's climax.

Her key relationships are primarily defined by her position. She has a formal, authoritative relationship with the Vox pilots, particularly Madoka, whom she confines to the base. She also engages with the adult commanders of Novumundus, using her authority to command briefings and investigate the anomalies surrounding the Vox Aura. While her relationship with the main trio of pilots is initially adversarial due to her restrictions, her later actions against Moid align her with their goals.

Regarding character development, Asteria begins as a strict and somewhat enigmatic leader, whose goals and the full extent of her knowledge are not immediately clear. Her decision to ground Madoka raises questions about her true intentions. However, by the second season, she takes a more direct and confrontational stance against the series' villains, demonstrating that her ultimate aim is to stop the larger threat. This progression shows a shift from a background authority figure to a front-line character in the resolution of the plot. Information about her notable abilities is not detailed in the available sources, with her primary assets being her intelligence, authority, and strategic mind.