Mitsuki, a female student, visits the house of Kenta, a classmate who is a shut-in. But when I press the intercom, no one answers. When she put the print in the mailbox and was about to leave, a man named Dango appeared. Dango introduces himself as Kenta's father and calls his son a ``poor kid.'' Mitsuki, angered by these words, ignores Dango's restraints and enters Kenta's room. Stand still