This song was sung by Wallow in the episodeSeason of the Mitch, the final episode in the second season. Wallow is making up words to the song as he goes along, and he is quite positive even though his arm was amputated.
Chris is missing,
Salami comes from farms.
Danny has low self-esteem,
And Beth cut off my-
It is assumed that the last word of the song is "arm", seeing as it rhymes, and that's exactly what happened.