Let's Go Play!(2006)

Asobi ni Iku yo!

Kio’s an ordinary high school student living in Okinawa. One day, he meets a cat-eared alien named Eris who claims to have come to Earth for an investigation. For whatever reason, Eris has decided to live with Kio and not only is she a freeloader, she seems to have brought a lot of troubles along as well… after much anticipation, this popular love comedy has finally been adapted into a manga!

(Source: Global Book Walker)