^
Geist is rated mature.. Golden Eye was also made by Nintendo, and that's mature. But that are actually all I remember.
Edit: Perfect Dark, Eternal Darkness (published, but developed?)
Also, there aren't exactly many mature 3rd party games on Nintendo plats either, on N64 there were 5...
Edit 2: Disaster Day of Crisis is mature by Nintendo, that could be interesting.
http://www.vgchartz.com/games/userreviewdisp.php?id=261
That is VGChartz LONGEST review. And it's NOT Cute Kitten DS













