Vampire Knight: Ice Blue no Tsumi  

Vampire Knight: Ice Blue Sin, Vampire Knight: The Sin of Ice Blue, Vampire Night: Season of Transience, ヴァンパイア騎士〈ナイト〉アイスブルーの罪

During the evening hours, a courageous student from the Day Class surreptitiously enters the forbidden Moon Dormitory of the Night Class students. Despite their disregard towards humans, Fuka was welcomed warmly and even invited back among them. There seems to be something captivating about her that has sparked interest in the Night Class, and once one becomes enamored with darkness, there is no going back...In the Extra Story, we meet Zero, a young vampire hunter who comes from a distinguished family. He has been trained under his master's guidance and was prepared for the challenges of life as a vampire hunter. However, when a senior disciple arrives, he discovers the harsh realities that come with being a vampire hunter. This event will forever change his outlook on life and leave him jaded towards the world.

Vampire Knight: Ice Blue no Tsumi was published in English as Vampire Knight: Ice Blue Sin by Chuang Yi on April 10, 2011.