You ruined it! That's the Tarantino twist ending, the part of the scene that is only showed at the end of the movie.
The first scene is me in a restaurant talking to my friend at a bar, telling him this poem.
Then my story unfolds as parts of my gruesome past and corrupted mind come clear slowly over the course of an hour and a half.
The final scene is me with my hair shaved off, naked and bleeding from numerous self-inflicted cuts in my bathroom, staring into the mirror reciting this to myself while flagelating myself with the final line added.
Then it pans over to my friends corpse in the bathtub.