Santarō Mita, relief pitcher for the Minato Tribe’s Extreme Baseball roster, cuts a striking figure with his long dark-brown hair secured by a yellow hair tie, sharp yellow eyes, and a habit of chewing a thin stalk. His casual ensemble—a yellow jacket layered over a white hoodie, black sweatpants, and white sneakers—complements his compact build and distinctively long eyebrows.

Brash and irreverent, Santarō boasts of ace status despite his reserve role, filling interactions with crude humor, taunts directed at Saori Arisugawa, and a penchant for sparking scuffles. Yet this rowdy facade masks steadfast loyalty to the Minato Tribe, whom he fiercely protects as kin.

In combat, Santarō leverages superhuman strength, acrobatic reflexes, and blistering baseball throws. His catcher’s gear deploys hypersonic-blocking forcefields, synergizing with his defensive role. Offensive and defensive capacities align at Small Building Level, while hypersonic+ reaction speeds mirror teammates like Shun Kamiya.

Gameplay casts him as a support tank: "Magic Pitch No.1 - Phantom" lures enemies while boosting ally evasion, and the Ultimate "Wild Pitch" disrupts foes with area damage. Though reliant on precise timing and overshadowed in raw power by higher-tier units, his balanced stats (1,574 HP, 277 Attack, 299 Defense) solidify his niche as a 2-star hybrid of defense and disruption.

His narrative arc remains static across media, prioritizing comedic clashes with Saori and unwavering tribal allegiance over deeper development.