Koi Kaze

Koi Kaze (恋風) is a Japanese manga series written and illustrated by Motoi Yoshida from September 2001 to October 2004, and was published by Kodansha's in five tankōbon volumes. An anime adaptation by A.C.G.T. premiered on TV Asahi from April 1 to June 17, 2004, and was licensed for North American release by Geneon Entertainment in 2005.

Plot
Born twelve years apart, siblings Koshiro Saeki and Nanoka Kohinata were separated after their parents divorced and growing up hardly remembering each other. When a 15-year-old Nanoka moves to Tokyo to live with her father and brother, she encounters Koshiro on the train after returning her train pass. Once met, they feel a brief spark of connection before they met again until they finally agreed to go on a date. It was then on a Ferris wheel ride later that the two finally opened their hearts and realizing their feelings towards each other, until their relationship faces against societal norms in the future.