Tomodachi Life (Also known as Tomodachi Collection: New Life in Japan) was released in 2013 for the nintendo 3DS. It is a sequel to Tomodachi Collection, A Japan exclusive Nintendo DS game, and one of the 5 games to use Mii's on the DS.
In the game, players can create new characters (Known as Miis), or import them, either from pre-existing ones on their console (Via the Mii Maker) or Via QR Codes (Either made through Mii Maker, which only fills out their face and base infomation) or through the game itself (Which adds things such as loved foods and clothing)
To scan a QR code, you will need to unlock town hall. This is done by the player creating a second Mii and them becoming friends.
Once unlocked, access the Town Hall, then select "QR Code" and then select "Scan QR Code"
Point the camera at the QR code, then follow the prompts.
"Too stubborn to quit, too stupid to die."
The sadistic, demigod cowboy comes to Tomodachi Life, minus his guns (Lucky for your other Miis!)
Unfortunately, there aren't many pictures of Caleb's face, meaning I couldn't make a very good recreation...