I'm looking for any manga, light novels, or web novels that feature a "reverse" world travel where a person from a magical world comes to earth. The elf is a Freeloader is an example: http://www.novelupdates.com/series/the-elf-is-a-freeloader/

series like Gate would do as well
Jikuu Mahou de Isekai to Chikyuu wo Ittarikitari (Novel) is another example... kind of

The Devil is a Part-Timer comes to mind.

Senpai will never notice you.

Anagle Mole off the top of my head.

Bokura no Kiseki

If you're all right with aliens...
Akatokisei Residence
Aura from Another Planet
Hitoribocchi no Chikyuu Shinryaku
Hoshi no Ponko to Toufuya Reiko
Kiss x Death
Ogeha
Tokyo Alien Brothers
Yome ga Kore na Monde.

And maybe...
Americano-Exodus
Spirit Circle