Someone who will spill their feelings (or uses other's emotion) to get money, publicity, etc. A lot of times emotion whores start making up emotion and overplaying it.
Some examples of emotion whores are talk show hosts and therapists.
Not to be confused with an emotion slut
who does because they can't shut up.
Oprah Winfrey is an emotion whore. She uses everyone on her show to get their emotions. That way people watch the show and she becomes filthy rich.