I’m not sure, but I think the answer is personification.
The lines from "Fable for When There's No Way Out" which have alliteration in them are the following ones:
his strength's inside him now
but his beak's too soft
if you break your head
in this round room
Still, stupidly he pecks
Rage works if reason won't
Alliteration, also called head rhyme, is the repetition of consonant sounds at the beginning of words in order to create different effects, such as drama or even humor.
A good writer cannot work well without a plot
