unnamed and young- no need for 'and' with two adjectives
character who- comma
Her “boyish” behaviors expand beyond the psychological level. Even her everyday activities reflect this quality. - I would be tempted to join these with a semi-colon
considered them- this should be singular to agree with 'work'
and responded- was this in response to what the father said? If not, I'd change the verb
be seen at near the end- be seen near the end
what a girl and a boy is- are??
hint of this occurred when the protagonist is- why not 'occurs' to go with the second verb?
pinned down in the arm- pinned down
bit more straightforward- bit more straightforwardly
behave gentle, act conservative and mind girl’s business- behave gently, act conservatively and mind their own business
soft spot for killing animals - logic??