This is Peter the elephant. Peter lives at Elephantstay, a non-profit program at the Royal Elephant Kraal & Village in Thailand. According to the uploader and piano player, PaulBartonPiano, Peter joined in “entirely of his own accord.”
It really does look like he’s smiling while playing! Make sure to check out the other elephant next to him, too. That one’s got some major booty moves goin’ on.