Nakai is a supporting character in the 2022 animated film Teasing Master Takagi-san: The Movie. He is a classmate of Nishikata and Takagi and is part of the close circle of friends that includes Kimura and Hamaguchi. Nakai is easily distinguished by his tall stature, short brown hair, and eyes that are usually depicted as closed. This characteristic is explained by his poor vision, which he does not correct with glasses in most appearances. His demeanor is calm and somewhat laid-back, and he often acts as an easygoing observer in the group’s daily interactions. While he does not tease or scheme like Takagi, he quietly supports his friends and participates in school activities alongside them. In the movie, Nakai appears in key scenes such as helping Nishikata with the class photograph session organized by Kimura and Takao. His primary motivation is simply to enjoy his middle school life and deepen his friendships. A notable relationship is his budding romance with Mano, a classmate and friend of Takagi. The movie subtly hints at their mutual interest, though their development remains understated compared to the main couple. Nakai does not undergo dramatic change in the film, but his interactions reinforce the theme of youthful bonds and growing affection. His main ability is his steady reliability, which makes him a dependable presence among the group. Overall, Nakai serves as a quiet but integral part of Nishikata’s friend group, contributing to the warm, nostalgic atmosphere of the story.