Keiichi Morisato, a student at the Nekomi Institute of Technology, is an unlucky but kindhearted young man who is constantly being taken advantage of by the seniors in his auto club. While doing some assigned tasks, an attempt to leave a phone message connects him to the Goddess Help Line and Belldandy, a beautiful celestial being who will grant him whatever he desires. The insecure Keiichi blurts out that he'd like a goddess like her to always stay by his side, and his wish is approved. Unfortunately, her presence quickly gets them both evicted from the male-only dorms, which only signals the beginning of his troubles, both mortal and immortal!