One day, a high school boy named Takeya Ikuhara found a girl who was one of the DearS, a group of aliens who, one year ago, had lost their way and found themselves on the planet Earth. The girl had fainted from hunger. Takeya took her to his home, and named her "Ren". She is called Ren Ikuhara in her school.
Ren likes Takeya very much, and always obeys him. She's constantly hungry and likes Melon bread a lot. Actually, she's a defective DearS and Miu teaches her everything. She's a pretty hot one and very famous in her school. She keeps on saying "Ren is Takeya's slave" which pisses off Takeya a lot. She does all the household work for Takeya and sleeps in a small closet in his room.
Later in the series, the other DearS come to know that she is the gate who is capable of destroying every living being on the earth. Will Takeya stop her from leaving the planet earth?