Oh Boy, Was I Wrong About Her

Oh Boy, Was I Wrong About Her is a romantic comedy based on light novels by Yu Hibari, with art by Shiso. It first ran as a free web novel on the site Shosetsuka ni Naro, from June 2020 to July 2026. Kadokawa Shoten published it in book form under its Kadokawa Sneaker Bunko label. The series ended in July 2026 with eleven volumes. Yen Press publishes the novels in English. There is also a manga version, drawn by Kina Oyama, with seven volumes. The anime was made by the studio Project No.9. It aired 12 episodes from July to September 2026 on Tokyo MX and other channels, and it streams on Crunchyroll.

The main character is Hayato Kirishima. As a child, he grew up in a small country town. His best friend back then was a kid named Haruki Nikaido. The two of them ran around outside, played games, and got into trouble together. Hayato always thought Haruki was a boy. Haruki was a tomboy, which means a girl who acts and dresses in ways people often think of as boyish. Then Haruki's family moved away, and the friends were separated. Before that, they promised to stay friends.

Seven years pass. Hayato moves to the city and transfers to a new high school. There he meets Haruki again, and he gets a big surprise. Haruki is a girl, and now she is one of the most beautiful and popular students at school. At first, Hayato does not even recognize her. Everyone at school sees her as a pure, elegant young lady.

The fun of the show comes from this gap. In front of other people, Haruki acts calm and graceful. But when she is alone with Hayato, she is the same playful, cheeky friend he remembers. She teases him, plays games with him, and goofs around just like they did as kids. Hayato is honest and a bit clueless, and it takes him time to see Haruki not only as an old buddy but as a girl he might love. Their friendship slowly grows into romance.

Other characters make school life lively. Himeko is Hayato's younger sister, who is playful and loves to tease. Minamo Mitake is a shy classmate who belongs to the school's Gardening Club, a club that looks after plants and flowers. Saki Murao is another childhood friend who has feelings for Hayato. With them, the story also touches on growing up, moving from the countryside to a big city, and finding your place.

The tone is light, warm, and sweet. There are funny misunderstandings and small, cozy moments. It suits viewers who like gentle school romance about old friends who meet again.