Kitano-sensei

Kitano-sensei teaches at Chihaya's high school and finds himself saddled with advising the newly formed karuta club, a game he knows little about and cares for even less at first. Awkward, mild-mannered, and faintly reluctant, he mostly hovers at the edges of the students' passion, present more out of obligation than interest.

He's the ordinary adult dropped into a story about teenage obsession, and the show uses him gently rather than mocking him. Kensuke Satou plays the hesitation and quiet embarrassment with real warmth, so the character's slow, unforced thawing toward the kids' enthusiasm feels earned rather than sentimental.