We're told Mowgli sang this song at Council Rock "when he danced on Shere Khan's hide" (6.1).
Mowgli is no Taylor Swift, that's for sure—his song has no discernable rhythm, rhyme scheme, or tempo.
He sings about how he killed Shere Khan, and then said, "lend me thy coat, Shere Khan" (6.12), before stripping the skin from the tiger's body.
He laments that the Man-Pack cast him out: "I did them no harm, but they were afraid of me. Why?" (6.18)—why then becomes a refrain, ending four of the last eight lines of the song.
Mowgli mentions how "the water comes out of my eyes" (6.23), and that he is "two Mowglis" (6.24), perhaps Mowgli the boy and Mowgli the man?
He concludes with "My heart is heavy with the things I do not understand" (6.26).