A reliable JK and a beautiful mother. Toshiro Nitta is a Hikikomori Neet who happens to be a trader. He lives alone in a large Japanese house as a shut-in. One day, some of his relatives have to start living with him ... !! The life of a heart-pounding harassing life begins!

From MangaHelpers:

Shibata Youichi is an ordinary high schooler, but one day he runs into a mysterious heroine! The cute girl knows his name, and (as in a stereotypical anime) she's an alien who needs him to help save her people! Soon enough, Youichi finds out that this situation was too good to be true... The girl, named Kyara, does represent aliens, but her people are actually interested in Japanese manga/anime/game culture. They want to use his home as a base and his brain as a measuring tool of the level of appeal of their heroines! [tethysdust]