April is the de facto leader and primary fighter of the all-female pirate crew aboard the spaceship Sol Bianca. Her full name is April Bikirk, and she serves as the first officer under the ship's captain, Feb Fall, though she frequently assumes the role of acting captain when Feb is too intoxicated to command. In the later series Sol Bianca: The Legacy, April becomes the official owner and captain of the vessel after inheriting the control pistol and recovering both the ship and the crew member June.

April is characterized by a strong, headstrong, and honorable personality. She often takes on a protective, motherly role toward the other crew members, watching over them and maintaining order when the situation requires a steady hand. Her behavior mirrors that of a classic space-faring hero, marked by a daring and determined spirit. She is thoughtful in her actions but can become as impulsive as her hot-tempered crewmate Janny when backed into a corner. April has a genuine love for adventure and danger; once her interest is captured by a treasure or a mission, she pursues it with unwavering resolve regardless of the risks involved.

April and Feb were the original pair who discovered the Sol Bianca, establishing a deep and long-standing bond that forms the foundation of the crew's dynamic. She is deeply protective of everyone on board, treating the crew less like subordinates and more like a family she is responsible for leading. Her relationships with the other women are complex, blending affection with the natural tensions of a tight-knit group living in close quarters. She has a particularly notable dynamic with the young engineer May, whom she takes under her wing, as well as with the temperamental gunner Janny.

Throughout the narrative, April's motivations are often driven by a desire to help others and a commitment to her own moral code. A central motivation for her is the recovery of a personal artifact: a rare flintlock pistol from the Frontier Age that holds clues about the lost planet Earth and the secret history of the Sol Bianca itself. Her role in the story is primarily that of the action-oriented leader, piloting the ship, engaging in combat, and making critical decisions during dangerous heists and confrontations with enemy forces such as the Terra Force.

In combat, April is exceptionally skilled as a pilot and a marksman. She wears distinctive red battle armor and favors a laser whip or a laser knife alongside a pistol as her primary weapons. Her abilities extend beyond physical combat to include sharp tactical thinking and the capacity to manage global situations effectively, often assessing and dominating challenges more quickly than her companions.