Tatsuya Tagami is a successful boss of a comic app. One morning, he wakes up and realizes that his private part has disappeared. Unidentified sightings of an object referred to as “sky fish” zips through the sky and make the local news. He accidentally comes across a mysterious club called Popran. The Popran are a group of men who have lost what they call their "popran" which have turned into flying objects. Now, Tagami only has six days to catch his high-speed "friend" or he will lose it forever.