You will know once he starts acting like a complete different person. If the kisses aren't the same or sex than question what is wrong with him. Or if he is making excuses frequently than usual.
Break up with him.
One word: Cheating.
He isn't cheating on her.
Justin Bieber is not cheating on her.
Try, I don't know, NOT CHEATING.
you will know if your cheating when you are dating someone and dating someone else at the same time.
i dont know
The Patriots did not cheat. Therefore they could not have known they were "cheating".
If they know about each other then no, it's not technically cheating.
Ask her if shes cheating on you! Nah im kidding i dont know sorry ? :( and im a guy
you stick your dick in his ear
Most likely in the same ways that you might know she was cheating with a man. It could even be less obvious, though, especially if she was cheating with one of her female friends.