Eiri Yuki is one of the main characters from the Shonen-Ai Anime: Gravitation. When Yuki meets Shindou Shuichi, who won't let go of him, they start a relationship.
He's cool, blond and bisexual (he had some affairs with women at the beginning of the Anime, but after meeting Shuichi it doesn't seem as if he had any other partner but him.) Apart from that he's really attractive and has amazing golden eyes. He works as a novelist, for lovestories, and is very popular. He is often very cold to Shuichi, but that is due to something that happened in his past (which we won't mention in more detail, you have to whatch Gravitation if you want to know exactly.)
Inoue Kazuhiko, who also acted as Seiyuu for Hatori Soma from Fruits Basket, lent his great voice this amazing character.
The reason why we are so fond of Yuki-san is because he's so terribly... HOT *lol*
*Information above came from Yuki Eiri Fanlisting: http://yuki.fan-elia.net/