Itazura na Kiss (1996)

Original title: イタズラなKiss

Late for a meeting, Kotoko was running along the corridor in school and bumped into Naoki, their lips meeting. Naoki showed his disgust, but Kotoko started to idolise him, who was good at everything from studies to sports. When Kotoko's house burned down, her father's good friend Machiko invited them to move in with her family. It was then that Kotoko realised Naoki was the elder son of Machiko, who took up the role of a fairy-godmother to bring the two together...despite the fact that Naoki was disgusted. Not discouraged, the clumsy and not-so-bright Kotoko started to do everything that would change her impression on him. Gradually, the icy-cold Naoki who disliked girls started to feel for Kotoko...