The opening stanza is very vivid. The maggots are ugly, disgusting, and yet, they have the potential to grow into something beautiful. However, the 'bleach' suggests that they must be cleansed of their ugliness--how interesting.

"And he saw something sick in me." OH MY GOD. Do you see how brilliant that connection is? You just compared the speaker to the caterpillar--a being of change and youth. Bravo! Wow! :D