I was actually playing for Soi, a 5 year elephant, when Peter came by with his mahout on his regular evening trip to the river for a bath. Peter heard the music and made deviation from the mud road (behind the tree) to the piano. I suddenly felt something strange sucking the back of my head and had an unexpected duet partner. In another video he plays piano and my back as a drum. The mahout you can hear occasionally isn't giving commands in any way to Peter, rather voicing a tiny bit concern for the piano's survival.