Given a category and a set of five words, find the word from the set that does not belong (i.e. is the least relevant) with the other words in the category. Words are separated by commas.

Category: emotional status 
Words: down, emotional state, loveful, ashamed, flat
flat

Category: emotional status 
Words: angry, joyful, tools, fearful, content
tools

Category: moral characteristic 
Words: fair, ok, tone, impartial, fine

tone