A glowing cube appeared out of thin air in the rental house of ordinary social worker Lin Dongmou, and he was forcibly bound to become a "trial guardian". His job is to help those unlucky alien creatures who have failed in various "trials" in the universe and unfortunately ended up on the earth to accumulate enough energy to return to their home planet. From a ball of slime that cannot be fed, to a crystal scorpion that uses vibration frequency to quarrel with people, Lin Dongmou has to carefully hide these extraterrestrial visitors, while also dealing with the charterer's life-threatening series of reminders and the never-ending flowers. He thought it was just a troublesome part-time job, but he slowly discovered that there seemed to be a huge secret behind these "lost items" that he could not imagine.
