3D Kanojo Real Girl is a Japanese live-action film from 2018, directed by Tsutomu Hanabusa and based on the manga series by Mao Nanami. The story centers on Hikari Tsutsui, a high school student and avid otaku who prefers the predictable world of anime and video games to his difficult real-life social situation. He is often mocked by his classmates for being awkward and withdrawn, finding solace only in his friendship with fellow otaku Yuto Ito.

Hikari’s life takes an unexpected turn when he is forced to clean the school swimming pool as a punishment alongside Iroha Igarashi. Iroha is a beautiful but enigmatic girl who is also an outcast, viewed with suspicion by other female students due to rumors about her being promiscuous and her habit of skipping class. Despite his initial distrust of someone he considers a stereotypical 3D girl, Hikari finds himself drawn to her honest and forthright nature. Iroha, in turn, is unbothered by his geeky interests and stands up for him when he is bullied. Their unlikely connection deepens, and Iroha confesses her feelings, leading the pair to begin a romantic relationship. However, their happiness comes with a critical condition: Iroha reveals that she will only be able to stay with him for six months.

The film follows the couple as they navigate the trials of high school romance, including jealousy, misunderstandings, and the development of a close-knit group of friends. This group includes Arisa Ishino, a girl who initially looks down on Hikari but later becomes a key ally, and Mitsuya Takanashi, a popular boy who initially antagonizes Hikari out of his own interest in Iroha. As their relationship matures, Hikari is forced to confront his insecurities and grow beyond his two-dimensional obsessions. The narrative builds toward the promised end of their time together, at which point Iroha reveals the true reason for their limited relationship: she has been diagnosed with a serious brain condition and must travel to the United States for a high-risk surgery that could erase her memories.

The story then advances several years. Hikari has graduated high school and become a successful working adult, but he still harbors feelings for Iroha. When she finally returns to Japan, the surgery was a success but, as feared, she has lost all memories of her time with him and their friends. The film’s final narrative arc follows Hikari’s determined but gentle efforts to reconnect with Iroha, to help her remember their past, and to prove that their bond can transcend even the loss of memory, leading to a final resolution about the future they might share.