to corrupt, backslide, degenerate

depravity, corruption, degradation

depraved (extremely wrong in a moral sense)

to act

action; behavior

he / distal demonstrative, something far off removed from both speaker and listener: that / boyfriend

distal demonstrative, something far off removed from both speaker and listener: that, yon / particularly, male personal third person pronoun: he / by extension from he: boyfriend

he; boyfriend

perfect, completed

(と〜) thinking that […] (with the next clause explaining that the truth is contrary to expectations)