Alicia Lopez is a member of the Neuron task force in Astral Chain. She is the master of the Beast Legion and is actually one of the first humans to have been given a Legatus with their own Legion by Yoseph.
Alicia was born in 2046, assumingly she was born on The Ark at that point as it was pretty much the only habitable place on the planet after the Chimera invasion in 2043. Alicia is known to be an old friend of Maximilian Howard, the adoptive father of the Protagonist and Akira, even if in reality she has romantic feelings fo Max that he seems to be completely obvious about.
She was given her own Legion sometine between 2076 and 2078 being one of the only three people able to use them at the time. She is first seen during the prologue of the story during which she cames to the twin's rescue alongside their father and Jin. After the twins recieve their Legion, Alicia investigate the scene of a kidnapping caused by a Chimera by her four other fellow Legionis.
During the mission, the Protagonist is dragged into the Astral Plane by Enceladus. The Protagonist seemingly defeats Enceladus but the Chimera actually trick him into lowering his guard only to shoot at him. He is saved by Maximilian, Alicia, Jin and Akira who followed them into the Astral Plane. Soon after, the Legions actually free themselves from their master's control due to the influence of the Astral Plane. Alicia fails to capture the Beast Legion back and is forced to flee with the rest of the group while Max is holding back the four rogue Legions as the Sword Legion was successfully captured by the Protagonist.
During the raid on the Ark Mall, Alicia and Jin are incapacited by the Arm Legion who takes Jin for itself. The Protagonist saves both. Alicia is then sent to the subway to help in rescuing civilians who were caught into accident pertaining to Chimera activity. While the Protagonist is rescuing civilians, Alicia gets into a fight with a pack of Beast Chimeras but the Protagonist eventually comes along to assist her. The duo then run into Deimos, which is immediatly identified as the source of the explosions that caused the accidents. Just after Deimos' destruction, they are attacked by another pack of Beast Chimeras led by the Beast Legion. The Beast Legion tries to drag Alicia into the Astral Plane but the Protagonist takes the blow instead and is dragged in her place and capture the Beast Legion soon after. Alicia regains a Legion after the defeat of Noah due to the repairs done to the Aegis Research Institute