What do you do if a friend you don't like tries to force you to kiss him in the mouth?

Kick him in the groin , so he can snap out of it.

Why would you have friends you don't like?

Knee in the groin and call the cops. That is sexual assault.

kick him in nads

If against your wishes, that is sexual assault.

I would slap him/her in the face. (I HAVE slapped him in the face.)

If he/she didn't immediately leave me alone, I would call the police and file a report. It's a shame to have to bother the police with this, but it's the "didn't immediately leave me alone" part that is important.

Oh, and he/she is NOT your "friend".

"...a friend you don't like..." Now there's a phrase.

Make the strength of resistance strong enough to dissuade him.

You should have kneed him in the balls.

First, I don't have any "friends I don't like".

Second, I only kiss my wife on the mouth.

Third, this has never happened to me.

I would deliver a solid punch to their jaw, I suppose. I have knocked out SEVERAL guys with a single punch (not a sucker-punch either. Never needed for a kiss on the mouth attempt).

defriend him immediately.

I'd pull away and ask him what the fvck he is doing