It's not okay to break a promise
Keith promised his roommate that he would help clean up the apartment.
Keith wants to go to see a movie.
Keith helps his roommate with the cleaning then goes to a late showing at the cinema.
Keith goes to see an early showing at the cinema leaving his roommate to do all the cleaning.
Keith's roommate is happy that they live with a person who shares the cleaning duties fairly.
Keith's roommate starts to dislike Keith for not doing his share of the cleaning as he said he would.