I believe it is around season 1 and season 2.
Episode one of vampire knight guilty
Yuki has a flashback about Zero joining their family in the second episode of Vampire Knight. In that episode, Yuki remembers how Zero was taken in by her father and brought to live with them after losing his family to a vampire attack.
in episodes 9 and above they show zero's past <3333333
That would be in the first episode.
sadly no. but that would be great!
Well, If Your Talking About When Zero First Bit yuuki, It Was At The End Of Episode 3
I think it is episode 8 when he turns her to a vampire.
vampire knight chapter 46 page 24
Zero has a gun that was given to him for vampire protection from the headmaster. He keeps it for that reason.
no
me kanamae
It is written on the first page of Vampire Knight manga chapter 24, on onemanga.com, that Zero Kiriyuu is 17 years old. * !*XD