The way the stanzas are structured, each one is like a limerick, so that certainly detracts from the darkness of it. It makes it light hearted, which could be really good but I know it's not what you were aiming for. Some of the rhymes are forced, some of the rhythm is broken and lost, but overall I enjoyed reading it. I like the fact the stranger was someone you cared about, it put a little twist to the tale, which is always good. nice work