Kazuya Saotome is a nerdy second-year engineering student at Ochanomizu Industrial University (お茶の水工業大学Ochanomizu Kōgyō Daigaku^?). His lifelong dream is to build a Doraemon (robot), and is trying to develop an artificial intelligence robot that happens to look like a toy squid. The story begins when Kazuya's wealthy rival, Kotaro Nanbara, gives him a computer program that supposedly will provide valuable information to help with Kazuya’s research and development. Actually, the program is a virus that Nanbara created in order to infect Kazuya’s computer and destroy his work. While attempting to fix his infected computer, Kazuya accidentally orders a "Cyberdoll" from the CyberdyneCorporation website. A woman appears at Kazuya's door with a small package containing a cyberdoll named Hand Maid May. May is a palm-sized robotic doll who is very sensitive and sympathetic to Kazuya's feelings, likes, and needs. The early part of the storyline focuses on Nanbara trying to get May taken away from Kazuya due to his inability to pay for her. Nanbara enlists the help of several other cyberdolls to attempt to take May away from Kazuya, but all of them end up falling for Kazuya and failing to retrieve May.

In the latter part of the anime, May is upgraded to a lifesize version of herself after Kazuya receives a visit from a mysterious visitor who wishes to promote Kazuya's artificial intelligence research. The situation complicates further when Kazuya's human friend Kasumi begins to get jealous of all the Cyberdolls flirting with Kazuya and they all compete to see who can go on a date with him. The last segment of the story deals with Kazuya and May having to deal with a virus which is shutting down all of the Cyberdolls, and a couple of mysterious visitors who turn out to be related to Kazuya and Nanbara in the future.