What can I do about this coworker?

he talks too much and will ask random questions constantly just to get me to talk. He plays to many games with people because he thinks it livens up the day or something. He also brings up immature lewd topics because he asked a question about if I have girlfriend or not which led to him asking do I have sex which led to him asking immature questions about it like "have you ever smelled p*ssy before?" What can I do about this ***hole before I end up starting a fight.