A Sign of Affection — Characters & Cast

Initially a wish to be understood without effort from others; this evolves into a desire to reach — to expand her world, learn what Itsuomi knows, and be an equal participant rather than a protected one.

Yuki begins as a university student with a carefully bounded life: deaf since birth, fluent in sign language, reliant on her phone and on friends who smooth the way for her. Meeting Itsuomi cracks that boundary open.

Over twelve episodes she moves from reacting to initiating — confessing, choosing, insisting on handling her own conversations — so that the finale's first date reads less as a reward than as evidence of who she has become. Some viewers argued the writing keeps her too soft and shy; others read that softness as a starting position the series steadily raises her from.

Curiosity about a person who communicates in a language he does not yet have; this matures from fascination into commitment and a genuine wish to close the gap on her terms.

A charismatic globetrotter who speaks three languages, Itsuomi enters as the confident outsider who helps Yuki on the train. His transformation is inward: a man used to motion and detachment discovers something he wants to stay for.

His decision to learn sign language is the series' clearest statement of love as labour, and a fan-favourite clip late in the run clarifies his real reasons for doing so. By the finale he is negotiating, apologising and adjusting — no longer merely the one who knows more.

To keep Yuki safe — which at first is indistinguishable from keeping her close, and gradually must be reckoned with as something closer to fear of losing her.

Oushi has known Yuki since childhood and learned sign language for her, which makes him uniquely able to speak with her and uniquely positioned to speak over her. He appears blunt to the point of cruelty, and his rivalry with Itsuomi openly split the fandom — some drawn to him, others reading his behaviour as controlling.

His arc across the season is one of diminishing leverage: as Yuki gains her own footing and Itsuomi learns to sign, Oushi's monopoly on her world dissolves, forcing him toward an honesty he has avoided for years.

Protecting her friend's happiness, complicated by her own need to be honest about what she wants.

Yuki's best friend and social anchor, Rin is the person who makes the hearing world navigable without making Yuki feel small. Her own romantic entanglements run in parallel, giving the series a second register of adult feeling.

As Yuki grows more independent, Rin's role shifts from buffer to peer — she stops smoothing the path and starts cheering from beside it.

Keeping the people around him from hurting each other carelessly, and gradually admitting his own stake in them.

Itsuomi's cousin and the most level-headed of the main cast, Kyouya observes the younger characters' chaos with steady detachment. He functions as the series' adult barometer, reading situations the leads are too close to see.

His significance grows as the emotional stakes rise, quietly nudging both Itsuomi and the supporting cast toward candour.