School Babysitters

The manga centers on the brothers Ryuuichi and Kotarou Kashima. Ryuuichi is in high school and Kotarou is still a toddler. After their parents are killed in a plane crash, the two brothers find themselves living with the chairwoman of the Morinomiya Academy, who herself lost her son and daughter-in-law in the same accident. The chairwoman, however, has one stipulation for the brothers in order to live with her: Ryuuichi has to work at the academy's daycare center as a babysitter. (Source: Anime News Network)

Daa! Daa! Daa!

Miyu is an 8th grade girl, whose parents have been hired by NASA. They take off to America leaving Miyu with Mr. Saionji. Later, Mr. Saionji decides to go on a 1 year long trip to India leaving Miyu alone with his son, Kanata. More complications rise when an Alien baby and his babysitter pet crashes/lands in their house. To make things worse, alien baby starts calling Miyu and Kanata Mom and Dad, also showing ESP power and floating around. (Source: Anime News Network)

PriPri Chi-chan!!

The story revolves around a girl named Yuuka, who encounters a being from the depths of the Earth named Chii-chan (a pun of chiteijin, the Japanese word for underground-dweller), and an alien named Ucchan (a pun of uchuujin or alien). The story follows their heartwarming and chaotic everyday lives together.

Potemayo

Sunao Moriyama finds a strange but cute creature that he names Potemayo. Potemayo starts following him everywhere, usually riding on top of his head. His discovery becomes the center of attention in his class at school. Soon after, a similar creature appears, and is named Guchuko by one of Sunao's classmates. However, Guchuko doesn't seem to be as good-natured as Potemayo. (Source: Anime News Network)