This is exactly the kind of web game I love. Deliberately simple style + engaging, creative gameplay + a wonderfully conceived, masterfully executed premise... checks all the boxes. Great work, on the color scheme and character design especially.
I think the rhyming couplets are a nice touch, it reminds me of similar verse by Gorey or Burton - accessible and a bit (knowingly) over-the-top, but tinged with darkness and with some real heart behind it. I definitely didn't expect the last line, and I was surprised at how much the last 'scene' made me feel. The only critique I have of the writing is that a few lines (I won't be specific, for the sake of folks who haven't played, but one includes the word "formidable") seem to wrench words into syllabic structures that don't match their patterns of enunciation, and unfortunately when that would happen it took me out of the experience for a second. There's certainly nothing wrong with the writing style, but a few of the rougher lines might warrant revision.
As a last note, I absolutely adore the music. Such a perfect soundscape for the theme and style of the game.