Sentarō Miya’s youthful features—light brown hair, matching eyes, and a petite frame—often lead others to mistake him for a middle schooler. His fiery temper flares when teased about his height, though he balances this intensity with emotional sensitivity, tearing up easily or growing flustered around girls. A memorable encounter with Satowa Hozuki even triggered a dramatic nosebleed.

Clashes with Chika Kudo erupt frequently, fueled by Chika’s accidental jabs at Sentarō’s stature. At Eidai High, he bonds with teammates Haru Kasugai and Akari Kobayakawa, their trio notable for stark height differences.

His name merges the kanji for “thousand” (千), “thick/great” (太), and “melodious/clear” (朗), while his surname Miya (宮) translates to “temple” or “shrine.” He savors yakiniku, dedicates school breaks to rigorous training, and regularly visits his grandmother and younger sister. Green peas and beans, however, earn his unwavering disdain.