Tsuki no ko Shoukougun: Ui Teru Bokura no Koi no Arekore

The gravitational pull of the moon causes the body to float, causing a condition known as "Moon Child Syndrome." This is a story of a "floating" child, woven by Tsukishima-kun, one of those affected, and Tsuchiya-san, a classmate. (Source: Akita Shoten, translated)