In a typical Japanese junior high school, Kashiwada is a girl with a perpetually blank face. No matter what happens, her expression never changes. Oota is her complete opposite, a boy whose every emotion is instantly visible on his face. Fascinated by her inscrutability, Oota makes it his personal mission to make her crack, pulling pranks such as fake spiders, surprise scares, and absurd text messages. His plans always fail because his own face gives away his intentions long before he acts. Unbeknownst to him, Kashiwada is not emotionless; she feels everything a normal girl would, from amusement to fear to affection. She simply cannot show it on her face, though her emotions are conveyed to the reader through small visual cues like arrows or text. In fact, she secretly enjoys Oota’s antics because she loves watching the parade of expressions on his face.

The two share a deeper connection. Years earlier in nursery school, a shy Kashiwada was isolated from the other children until Oota pulled her into their play. Before she could thank him, his family moved away. Now reunited in middle school, Oota does not recognize her, but Kashiwada remembers everything and has harbored a quiet crush on him ever since. That childhood backstory slowly emerges over the course of the series, adding a layer of sweetness to their daily bickering.

The story unfolds in an episodic, slice-of-life fashion, following the seasons of a school year. Early arcs focus on Oota’s failed pranks, Kashiwada’s unreadable reactions, and the amused commentary of their classmates. Notable episodes include a pool-cleaning day where Oota tries to startle Kashiwada with a water squirt; a visit to a haunted house where he ends up more scared than she is; a Christmas party where a surprise gift goes wrong; a Valentine’s Day chocolate exchange that leaves both of them flustered; and a summer festival where Oota impulsively declares himself her boyfriend to ward off a creepy man. The story also covers beach trips, study sessions at the library, a white-day return gift, and a school sports festival.

Side characters add richness. Tadokoro is Oota’s loud best friend who often becomes the victim of his schemes. Sata is the cool observer who enjoys watching their dynamic. Tabuchi is the class representative who adores Kashiwada and sees Oota as a rival. Odajima has a mysterious ability to read Kashiwada’s hidden emotions and acts as an unofficial interpreter. Oota’s playful older sister enjoys meddling, and Kashiwada’s overprotective older brother is wary of Oota. The strict teacher Oniwarada frequently scolds Oota for wearing his heart on his sleeve.

Although the series is primarily a comedy built on repetition, it slowly develops the romantic tension between the two leads. Kashiwada’s subtle feelings become more apparent to the reader, and Oota gradually shifts from pulling pranks out of curiosity to genuinely caring for her, even if he remains too embarrassed to admit it. The manga ends with their relationship still in a delicate, unspoken state, but the spin-off series Inexpressive Kashiwada and Expressive Oota+ continues their story through middle school summer vacation and into high school, giving fans more of the heartwarming, funny, and quietly romantic moments that define the series.