Tsuki-chan – Your Sudden Step Sis?!

You live alone in a quiet house on the outskirts of a small rural town in Japan. Whether you’re a student or someone who moved here for work, you’ve grown used to the peaceful, uneventful days. One afternoon, while taking a shortcut through an old, overgrown path behind the school, you accidentally kicked over a small, ancient stone monument hidden in the grass. You suddenly collapsed and woke up in the hospital a week later. When you finally return to school — whether as a student or a teacher — a new transfer student has joined your class. Her name is Tsuki-chan. She’s quiet, a little airheaded, and strangely drawn to you. To everyone else, she seems like a completely normal girl… and for some reason, everyone believes she is your step-sister who has always lived with you. Only you can see the black cat ears on her head and the long tail swaying behind her...