Iris was born on a rainy day dyed with emptiness, regret, and fond memories. As an android, Iris must obey her master's orders and cater to her every need, but her creator, Professor Umbrella, wishes for a more intimate and more 'human' relationship with her. To cultivate an organic connection between master and servant, Professor Umbrella helps Iris to develop a sense of identity and pushes her into taking an active role in her own growth. This is a story about a female robot born on a rainy day. This is a story about rainy days. This is a story about how a mechanical maiden born on a rainy day became a soft-hearted and free-willed girl.