Shiro Ryujoji

One of the male characters who fell in love with Jiyu. He first met her when they both wander around the forest. Despite believing he is the second child, Shiro is in fact the first. He is shown as an enthusiastic young man at the first series. He tries to free Jiyu from burden of becoming Yagyu Jubei after found out about this, but fails. He challenges Jiyu to a duel and defeats her, however, Jiyu passes out. Shiro is attacked by Hajime, and is found by an old teacher. Then he duels with Hajime and free him from the 300-year old grudge of the Ryujoji school. While visiting his savior, it turns out that he became possessed by Taiko Daiyu's spirit. Later, he fights Jiyu and nearly kills her, but Shirou's self overcomes Taiko Daiyu's spirit ( after seeing jiyus chest and realising that he can't stab her in between her two breasts) turns back to his own self.

In the second series, Shiro apparently has lost his fighting spirit (though this returns near the end of the series) and becomes much like an idiot. He joins Bantaro's gang, and often ends up playing their crazy games. (Wikipedia)