A Desperado

1. A bold outlaw, especially one from southern portions of the Wild West.
2. (colloquial) A person in desperate circumstances or who is at the point of desperation, such as a down-and-outer, an addict, etc.
3. (colloquial) A person who is desperately in love or is desperate for a romantic or sexual relationship.
4. (chess) A piece that seems determined to give itself up, typically to bring about stalemate or perpetual check.