Keiichi Morisato is a good-natured, yet hapless and girlfriend-less college freshman who is often imposed upon by his elder dorm-mates and brow-beaten into taking phone messages and doing miscellaneous chores for them. One day, while alone in his dorm, he accidentally calls the Goddess Technical Help Line and a beautiful goddess named Belldandy materializes in his room. She tells him that her agency has received a system request from him, so she has been sent to grant him a single wish. Skeptical and thinking someone is playing a practical joke on him, he wishes that she stay with him forever. To his surprise, his wish is granted. Belldandy must stay with him, but as his dormitory is strictly male-only, they are both forced onto the street.