He wont kill, she wont die Japanese film

Rei Kosaka (Shotaro Mamiya) is a 3rd grade high school student. He
is not interested in anything and lives a boring existence. One
day, Rei Kosaka sees his classmate Nana Kano (Hinako Sakurai)
burying a dead bee. He takes an interest in Nano Kato, who
carefully deals with a bee's life, because she keeps telling him
that she wants to die.