Summary from Iskultrip Scans:

Story 1 (Phantom Lim): Lim and Iota live in a robot country. Lim, who is in love. Iota, whom she loves. The kind robotic maids. Lim has always thought her sunshine-filled days would go on forever, but... what is this promise Iota made with her in the past and the secret that he's keeping from her?