Making someone feel obligated, pressured or forced into doing something of a sexual nature that they don't want to is sexual coercion. This includes persistent attempts at sexual contact when the person has already refused you. Nobody owes you sex, ever; and no means no, always.
You can always evaluate a man's character by the way he speaks about his ex girlfriends and other women. When entering a new relationship or getting close with a new guy, make sure you take notice of the language he uses when referring to other girls