Koku
黒羽, Black-Winged King, Killer B
253
Gender:Male
Koku is one of the main characters in B: The Beginning. He works as a Violin Craftsman under Lilys father and has the ability to transform into a blackwinged heteromorphic being. He is also the true identity of Killer B a name derived by his unusual way of writing the number 13 at his murder sites.
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