The story revolves with Tsukushi Makino, a working-class girl and the F4 (flower four), the most popular and rich children of the Eitoku Academy.
The F4 leader and son of the wealthiest, most powerful family in Japan, Domyouji Tsukasa, takes an interest in Tsukushi, because she is the only girl at Eitoku who does not fawn over him. However, his hot-headed nature and bullying ways is originally a major turn-off for Tsukushi, who has her sights set on Hanazawa Rui. Hanazawa Rui, Tsukasa's best friend, is a quiet and cold guy, but he has a soft spot for his close friend and Tsukushi's idol, the model Todou Shizuka, whom he harbored feelings for since childhood.
The other two members of the F4 are Mimasaka Akira, the laid-back peacemaker of the group, and Nishikado Sōjirō, an unrepentant playboy. They both usually have at least one girlfriend at any one time; Akira prefers older women because the women of his household (his mother and two younger sisters) are quite silly. Sojiro is happy to be in casual relationships with many women, although we later discover that at one time he was in love with a childhood friend.
Over the course of the series, however, Tsukushi's feelings evolve, and she begins to appreciate the degree of change that occurred in Tsukasa once he fell in love with her. He becomes fiercely loyal to Tsukushi and believes in her beyond all doubt, and slowly gets her to see him in a different light.
This is the best love story I’ve ever seen. The series is a combination of drama, romance and comedy, also a bit of action. The mood can be slow and gentle, or intense and frightening. All characters are interesting and the music is great. The series is much like a teen soap opera. The voice acting is interesting, and the character designs are unusual. The color scheme of HYD is unusual as well. The colors are very muted and soft. There are lots of pale yellows, cream, grays, blue-gray, and browns. I think this lends the series a greater sense of reality. Anyway, if you should come across this series, I highly recommend checking it out.