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: sad, remorseful, down, ashamed, sliding
sliding

Category: direction 
Words: kind, descending, down, opposite of up, flat
kind

Category: emotional display 
Words: identity, fawn, cub, follow, love

cub