推理作家「M」尋找在萬聖節的晚上消失的戀人的同時，與各種奇妙的人陸續相遇。最後 M 將迫近女朋友失蹤真相的核心，迎來意想不到的事態。

Makoto, who doesn't get along with her boyfriend, family, or friends, goes camping with a childhood friend she meets again, but... "We're just bored," Makoto murmurs, and the way she lightly and deeply empathizes with her overwhelmed heart is exquisite.