Comic books at the commercial end of the scale are mostly the stuff of fantasy. Marvel didn’t build its universe and Osamu Tezuka didn’t become the “god of manga” with tales of the everyday and familiar. However, some comic creators — Harvey Pekar in the United States, Yoshiharu Tsuge in Japan — developed more personal, realistic approaches that won critical kudos, if not big checks for movie rights.

In Takahiro Horie’s “Sensei, Would You Sit Beside Me?” Sawako Hayakawa (Haru Kuroki) is a successful and in-demand artist who thrills her perky, all-business editor, Chika (the single-named Nao), with an idea for a series based on her own life, her troubled marriage included. To her husband’s dismay, her new manga seems drawn directly from her daily existence, almost word for word and revelation by disturbing revelation.

But how often does such an autobiographical story get greenlighted in the real world of big-time manga publishing? Almost never, and yet the film, which Horie scripted from his own award-winning treatment, smooths over its improbabilities with clever plotting, crisp relationship comedy and a fresh take on an age-old theme: adultery. It’s almost too slickly well-made for its own good, but as the story becomes more complex, Sawako’s pain deepens and her anger intensifies. Instead of light entertainment of the smarter sort, the film becomes a piercing look at what makes a marriage survive — or not.