[ That's okay because 9S has no musical experience whatsoever, so whatever Finn is playing is what 9S assumes is righty tighty. He tries to follow along with the pips of the flute, while also following the general ups and downs of the sheet music, and everything is probably wrong. He can sing on pitch; it just doesn't amount to much when he has only a vague idea of what the right pitch is. He keeps trucking along though, because he's willing to ride this trainwreck to its natural conclusion. ]

♫ You know Dasher and Dancer and Prancer and Vixen ♪
♪♪ Comet and Cupid and Donner and Blitzen ♪
♫ ♪ But do you recall ♫
♪ The most famous reindeer of all? ♫
[ ... ]

[ And so on. One could describe his singing as a minute-long question mark. ]