Murray Leinster: If You Was A Moklin
You'd love Earthmen to pieces, for they may look pretty bad to themselves, but not to you. You'd even want to be one!

Moklins are the friendliest aliens humans ever encountered. They LOVE humans, and want to imitate them in every way they can. And evolution on Moklin is very helpful in this regard and extremely fast. After 40 years on Moklin, the humans on the planet enjoy the friendship of these helpful 'people'. There might be one little problem though. Just a tiny thing that will cause the humans to leave in a very big hurry. Not that it will do any good of course. The Moklins love us.