After losing his wife to an incurable illness, he worked tirelessly to create a medical phenomenon. Unfortunately, the night he finally finished his discovery, Vampires attacked his house. Kisuke was transformed into a vampire by Agatha and attacked the Jaegers, he ended up getting killed by Yuliy right before he attacked Saki, his young daughter.
Saki was Kisuke's young daughter whom he had with his late wife before her passing. He regrets not spending as much time with her as he wanted to.
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