Sumika Kagami is a central character in the Muv-Luv Alternative visual novel series. She is a childhood friend of the protagonist, Takeru Shirogane, and plays a critical role in the narrative. Sumika is known for her energetic and cheerful personality, often bringing a sense of warmth and familiarity to those around her. Despite her bubbly demeanor, she harbors deep feelings for Takeru, which become a significant driving force in the story. Her character is pivotal as she becomes entangled in the complex events of the series, revealing her resilience and emotional depth.