Shinobu Kocho age is18 Years Old. Shinobu Kocho died in the final arc of the manga, during the battle against Muzan Kibutsuji, the main antagonist and the progenitor of all demons. She sacrificed herself to weaken Muzan by letting him devour her, knowing that her body was infused with a large amount of wisteria poison. Her death was a crucial part of the plan to defeat Muzan, as it allowed the other demon slayers to inflict fatal wounds on him.