The catlike aliens known as Nyanbo are looking for pieces of their UFO so that they can to return to space. Sometimes they get tired of searching however and just wish to play around like actual cats.
The show primarily features live action visuals (including real cats), with only the Nyanbos themselves being animated. The comedic style ranges from slapstick to romantic comedy.
More Information:
aniDB
Crunchyroll
Wikipedia