From Attractive Fascinante:

Kijimuna, an Okinawan fairy who lives in a banyan tree. About the same height as a young kid, with reddish skin and hair. They will come down from the tree and do naughty things to humans at night. You’ll get happiness if you nurture it and the fairy will never betray you. Tomohisa bought a potted plant that comes with such a resident, Kite. When feelings gradually develop between them, Tomohisa’s senpai and ex-lover, Kazunori, wants to reconcile with Tomohisa. Will Kite try to stop it from happening or will he let Tomohisa choose his own happiness?