There is this guy who is friend of a coworker.
I would just keep telling your co-worker, no, you're not going to meet the guy. Stand firm and don't let your co-worker bully you into it. You gave the other guy a chance by meeting him. Then, when he told you he just wanted to misbehave with you, you gave him a chance to take it back, and he didn't. Your co-worker didn't even try to argue that his friend might be joking or might be willing to take things slowly for the right girl. It's clear this guy is thinking about things that you don't want to offer. You shouldn't be pressured into that or even into being around him when you know he is thinking that way. There is no point in seeing him when you already know what he has to offer is not what you want.
Not all men are like that. There are still a number of men today who want to take things slow and get to know you and build a relationship first. This guy is just not one of them. I would stay away from him and ignore your co-worker.
If I were you, I wouldn't meet him!!!