Il-ho, the satellite ‘KITSAT-1′, is launched into space. She observes Earth over a long time and becomes curious about the human heart. Kyung-chun, an aspiring musician, is heartbroken and is turned into a milk cow by dark magic. One day, when Kyung-chun is in danger from the Incinerator who attacks those with a broken heart, Il-ho hears his song from earth, and comes crashing to the ground and in the process, becomes human. Now on earth, Il-ho comes to Kyung-chun’s rescue whenever he is in danger.
As the two become close Il-ho begins to slowly understand the human heart, and can help Kyung-chin find a way to become human.