I love the comparison to the struggling rat that refuses to go down swinging. the third section really hits home with the rat ignoring the problems of "the universe" and just fighting on. a little bit of criticism I have is the last two lines, it changed from talking about the rat to first-person and it felt like it was sort of just thrown in at the end. i felt like the rest of the poem already implied what the two lines said and they didn't really need to be there. other than that, this poem gave me goosebumps

I love this poem. The way it builds to the end is so fitting. The formatting of the stanza about the rat is also very well constructed visually, it actually reminds me of a person taking a deep breath. Your word choice is fantastic as well. All of that build up to end on a very punchy last hook (figuratively and literally) is very satisfying. It already feels like a polished poem, so I'm not sure there's much for me to say. I do think that the "half-man-half-beast" was a tad clunky, but it still feels like it fits the way the narrator is speaking. 

Well done!

You wake up still entombed in yesterday.