Deaimon(2016)

Deaimon

Nagomu Irino returns to his Kyoto home for the first time in ten years when his father is hospitalized. Nagomu is eager to take over Ryokushou, the family's Japanese sweet shop, but he's instead asked to be a father figure to Itsuka Yukihira, the girl everyone calls the successor.

(Source: Manga Translation Battle)