This is the pancreas one btw https://myanimelist.net/anime/36098/Kimi_no_Suizou_wo_Tabetai
Kimi no Suizou wo Tabetai
Spring time in April and the last of the cherry blossoms are still in bloom. The usually aloof bookworm with no interest in others comes across a book in a hospital waiting room. Handwritten on the cover are the words: "Living with Dying." He soon discovers that it is a diary...
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