Well...for me....my limits change based on the person I'm with. Some people can motivate me to go further, while others are so uncomfortable with their own sexuality (or with me) that they make me nervous to be around them.

I also think limits depend on the situation.

Watch the body language of your partner...you'll (hopefully) get a good sense for what they want.

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Life is too short not to love and be loved....preferably multiple times in one night.

I think men talk to women so they can sleep with them and women sleep with men so they can talk to them. ~ Jay McInerney