In Cardcaptor Sakura
Touya is the brother of Sakura Kinomoto. His birthday is on February 29th, which makes him a leap year baby, a person that can only "properly" celebrate their birthday once every four years. He holds the belief that as Sakura's older brother, he is the only person entitled to make fun of her, a belief that his best friend Yukito Tsukishiro refers to as a "sister complex." However, he is also protective and caring of her, which leads him to dislike Syaoran Li when he finds Syaoran cornering Sakura in the schoolyard. Though Syaoran and Sakura eventually stop fighting, Toya continues to dislike Syaoran when he becomes friends with Sakura, knowing that Syaoran will eventually take Sakura away from him. He is a perceptive young man and has had a vague idea as to what Sakura has been up to as a Cardcaptor, despite Sakura's attempts to keep it a secret.
Toya's main relationship is with his best friend Yukito. Throughout the series Toya and Yukito are extremely close and eventually Yukito openly admits his love for Toya to Sakura after Toya saves his life.Toya was born with some magical ability, allowing him to see ghosts (including the one of his late mother). His magical ability is also what helps him sense when Sakura is in danger or when she is doing other "magical" things (which enables him to follow her).
In Tsubasa Chronicles
Touya is the current king of the Clow Country, but he acts pretty much the same as he did in Cardcaptor Sakura.
(Source: Wikipedia)
