There are some kinds of VK ending that might be happen:
1.Kaname dies,Zero and Yuki lives but don't cinta each other.
2.Zero dies,and Yuki follows him(it means she dies too!)
3.Zero and Kaname fights to have Yuki and both die,Yuki's alone
4.Yuki realized that she just admires Kaname and doesn't cinta him,and her real cinta is for Zero=>she comes back with Zero.
5.Kaname and Yuki dies,Zero lives and loves Sayori,or lives and alone.
6.Kaname dies and Zero kills Yuki,then he kills himself.
7.Yuki kills Zero and Kaname.She kills Zero because she really wants his blood,and kills Kaname because of his guilty,and after doing all she killed herslef.

Season 1:From vol 1 to vol 9:It tells about the stories between the hari Class and the Night Class of menyeberang, salib Academy,which has the main characters Yuki Cross,Zero Kiryu and Kaname Kuran.Yuki and Zero are hari Class students and Kaname is the leader of Night Class students.In this season Yuki and Kaname have feeling for each other.Zero is not a normal human,he is also a vampire who is biten oleh pureblood Vampire Shizuka.He loves Yuki too.But in vol 8 the hidden truth is leak,Yuki actually is Kaname's younger sister and a pureblood vampire.Zero,as a hunter,must be enemy of her.In pureblood families,brothers are allowed to marry.
Season 2:From vol 10:Zero and Yuki beats Rido Kuran,a crazy pureblood vampire,and before Yuki left the Academy with Kaname she and Zero have a sweet ciuman and she knows that she also loves Zero.Now the stories turn:It doesn't tell about hari Class and Night Class.Actually,it tells about vampire and Hunter Association.The story now is becoming exciting...