WARNING: The following contains spoilers for Episode 7 of Komi Can't Communicate, "It’s Just the Pool," now streaming on Netflix.
Shoko Komi is a high school student who struggles to verbalize her thoughts and feelings, and up until this point, it’s been assumed to be due to her extreme social anxiety. Episode 7 of Komi Can't Communicate, however, reveals this may not be entirely the case. When viewers are introduced to Komi's father, Masayoshi Komi, it's immediately clear he too struggles with a communication disorder.
Sometime after Komi's outing with her friends to a water park, Komi decides to visit a public library to check out a book. Her father decides to escort her, though he doesn't verbalize this decision at all. Instead, he looks his daughter in the eye and she immediately understands what it is he wants to do. This form of “telepathic” communication between father and daughter is a mystery to Komi’s mother, Shuko.
On their way to the library, Komi and her father look straight ahead, never uttering a word to one another. When they come across a shop that sells shaved ice as a snack, both come to a complete stop. Masayoshi signals to Komi that he wants to treat her to some shaved ice, which she silently accepts. Inside the shop, other customers notice that both father and daughter are good-looking but don't speak at all, which causes them to misinterpret their behavior as hostile.
During the ordering sequence, both Komi and her father use hand gestures to communicate their orders to the server; however, the latter doesn't shake with anxiety in the presence of others. This indicates that Masayoshi's communication disorder is not due to paralyzing social anxiety as in the case of his daughter. Instead, it seems to suggest a different severe anxiety disorder such as selective mutism where an individual is unable to speak only in specific situations. This is most notable when the father is able to verbalize a question to his daughter about how she's doing in school, whereas Komi would've needed a notebook and pen to make that inquiry.
More differences between father and daughter become noticeable in the latter half of Komi Can't Communicate Episode 7, when Komi goes about the rest of her day. As mentioned earlier, Masayoshi doesn't shake with anxiety in the presence of others. He is able to remain relaxed and carry on with his day even when he's being observed by people. He also maintains a stoic face, which is harder to read and makes it more difficult to figure out what he's really thinking. This causes others to misinterpret his behavior as standoffish or unfriendly, even though he’s actually a nice person.
Komi, by contrast, tends to wear her anxiety on her face and hates being stared at. This causes her eyes to widen and she either freezes on the spot or her body starts to tremble. It's especially notable during her trip to the library, where she gets noticed for her looks and immediately shakes when she sees people commenting on her appearance. Even when she tries to sit down to read a book in the library to calm her nerves, her anxiety flares up again when a baby starts crying next to her. When she tries to calm the baby down, her efforts only cause the baby to wail even louder, which exacerbates her anxiety. It's not until the mother walks away with the baby that the latter finally calms down and waves at Komi.
When Komi stops at a local park later in her day, she decides to play on the playground -- but only after checking her surroundings to ensure no one else is around to witness her. After assuring herself the coast is clear, Komi proceeds to do everything she wants from going down slides to dangling off monkey bars to swinging on swings. Even then, however, she remains vigilant of her surroundings. This indicates that while there appears to be a genetic link between Komi and her father that predisposes her to be mute in social situations, it also appears to happen as a result of a different type of anxiety than the one Masayoshi experiences.
