It’s the mushroom dude from Osawari Tantei , Mystery Detective / Touch Detective from NDsi game. The game is also available on iOS. Osawari Tantei is a point-and-click mystery adventure game for the Nintendo DS which makes use of the device’s touch screen.
It was developed by BeeWorks and released in Japan by Success Corporation. It was developed and released in the United States by Atlus, and in Europe by 505 Games. Touch Detective was released for the iOS on August 4, 2011. Its first chapter is free to download.
If you don’t have a clue of which type of mushroom than perhaps this video will help you understand