Mikage Sakurai, a third-year geology student and vice-president of the Earth Sciences Club, balances sharp wit with quiet devotion to her peers. Her shoulder-length red hair and crimson eyes mirror her fiery passion for geology, a subject she champions by distributing "lucky rocks" to entice newcomers. Though outwardly stern, especially toward unfamiliar faces, her younger sister Chikage observes her hidden warmth toward clubmates. Mikage fiercely upholds principles, refusing to replicate the astronomy club’s cosplay booth to preserve originality, yet her resolve wavers when confronting her own uncertain ambitions and quiet envy of risk-takers.

Once resistant to the merged club’s astronomy-focused activities, she gradually acknowledges their value, marking a shift in her rigid perspective. Post-graduation, she relinquishes her role to Chikage, ensuring her legacy within the club. Her name, derived from "beauty" and "scenery" with a surname meaning "cherry blossom well," reflects her grounded yet aspirational nature. Despite academic diligence, occasional clumsiness undermines her efforts, and her no-nonsense demeanor contrasts with peers like Mari Morino. Beneath her guarded exterior lies a steadfast commitment to the club’s unity and the quiet well-being of its members.