In most relationships it certainly would be over the line because it often accelerates the mind sex games which often lead to going all out eventually.
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Serious dating or casual??? by: Anonymous
I've been dating my boyfriend for over a year and we are getting married when we get a bit further in college, however, we are not engaged yet. Even before we were this serious we were seeing each other exclusively.
I personally feel if you are dating someone exclusively and they kiss another person then it is definitely grounds for breaking up with them.
If you are just casual dating then I think it doesn't matter as you are not obligated to that person.
BUT!!! As you said, each situation should be taken into consideration.
But personally if my boyfriend ever kissed another girl after all the promises he's made me, I'm pretty sure I'd die on the inside. If you're dating someone who truly loves you, they wouldn't be in that situation in the first place.