I like Zero because I feel so bad for him. He is a vampire, which he depsises. He can't help it either and his life sort of sucks. I sorta sympathize with him. Plus he is SMEXY. I also love his attitude.
At the first manga and first night,I love him because he is so cute^^
At the next nights, Ilove him because he is so thirsty blood vampire
And the next,I love him because I can see his hurt and fear when he became vampire
And the next,I love him because he really undersands Yuki
And finally,I love him because he loves Yuki and ready to do anything for her.He is gentle and isn't selfish too.