One year ago, an alien spacecraft crashed into Tokyo Bay, leaving the crew stranded on Earth. The aliens are granted Japanese citizenship and begin a home-stay program to learn about human culture. When one DearS goes astray and wanders into the life of a high school student named Takeya, the adventure begins and this DearS is about to learn things they don't teach you in school!

Miu decides to depart her Earthly domicile and challenges Ren to a final duel. Next up, Neneko needs models for her costumes and she recruits Ren and Miu to do the job, leaving Takeya tongue-tied before the bountiful beauties. And when Miu wins a local contest, everyone enjoys a trip to the hot springs resort, where the water isn't the only thing boiling over.

Takeya worries that he will be held back if he doesn't pass his midterms, so Miu takes the initiative to lead a study group in his apartment. Little does Takeya realize that there are larger forces at work in the universe that will affect his life in ways unimaginable to him. Ren has been recalled as a defective DearS and, not wishing to return to the DearS ship, Ren runs away only to discover what the true meaning of community is.

Aliens called "DearS" have landed on Earth and are now a normal part of society. In order for the "DearS" to learn Earth's customs, they are sent to random high schools to "home-stay." When Takeya helps a DearS in his school, she calls him "Master." Thus begins the humorous life of Takeya and his sexy alien follower, Ren, who tries to figure out the wacky customs of this place called Earth!

Can life be any better for Takeya? He's surrounded by three beautiful women: Ren, Myu and Neneko. Unfortunately, some things can be too good to last when a DearS agent arrives to take Ren away as a defective slave. She will have to learn free will if she truly wishes to demonstrate to the rest of the DearS community that she really wants to stay with her new master.

Meet Nia. Her trainer Xaki is teaching her to be a Biter. She looks up to her trainer, and will do anything for him, including tracking down some Zero Number named Ren! When word gets out that Ren escaped from Xaki when he tried to bring her back to the community, Nia sets out to avenge the dishonor done to her trainer. Meanwhile, Ren is getting more attention from class playboy Hiro.

When Takeya rescues Ren from DearS dominatrix Barker Rubi, the trauma has caused her to lose her Japanese language skills. The cure? A little R&R, of course! They take a class trip to the resort town of Bousou, where the beach bum DearS Ayu tries to help Ren recover with a game of high-flying beach volleyball.

The new school term has started for our heroes and between needing to help Ren get changed into her uniform and Hiro-kun still making all the moves on the oblivious alien, Takeya's plate of stress and trouble is nicely topped with a surprise visit from Miu who is desperate to return his sharp-pen to him.