From the perspective of an alien planet with super-advanced technology and tiny (1/60th the size of a human) inhabitants, planet Earth was the perfect location to banish their worst criminals. Five of said criminals were sent to the planet to be exiled, attached to little critters like frogs and rabbits so they can never be fully active. Due to an accident, these five criminals managed to escape and attach themselves to five different girls that were nearby. The one responsible for the banishment of these five criminals now must detach them from the girls by mouth-to-mouth release.

(Source: MangaHelpers)

Shinjou wants to enter high school as a new man, since he had not been very popular back in Middle School. As he's trying to edge his way into society with his new look and personality, he happens to bump into Kurai Kako, a classmate from Middle School who had been just as invisible as he was. With her new look and personality, has arrived for just the same reason he has, and she's looking forward to snagging a boyfriend for high school. They'll just have to make a bet -- who'll get a boyfriend/girlfriend first?
(Source: jCafe24)