Sex is about consent with that being said if you do not consent, it's rape. NO ONE (not your husband/wife, girl/boyfriend, best friends, or anyone else) has the right to force you to do anything you do not want to do after you've said NO. It's your body you have the right to do with it as you please. Be cautious of people who use GUILT, BLACKMAIL, DISAPPOINTMENT, LOVE, or ANGTHING ELSE as a trick to get sex out of you. If you don't want it, it's rape. I've heard every line a man can shoot at you for sex - "but don't you love me" "just this one time" "but you did it with *insert name here*" "why (begging and pestering)" "I guess you don't care about our relationship" "it's your fault I cheated because you won't" "I'm so upset about *insert bullshit excuse here* I just need you" "I can make you feel beautiful" etc etc etc - no means no. If he can't respect that than no can also mean bye. If he loves you he can wait (trust me on this their masturbation method is far less complex than ours) if he loves you he wouldn't want to make you feel uncomfortable and most importantly if he loves you he will understand.