PLEASE ANSWER!!! What do you think of this guy I work with?

I think you made the right choice by not wanting to see him anymore. If this is your first date everything he does will be first impressions. One of his first impressions was to steal and yes, that is bad bad, so bad. He clearly doesn't want or is interested in the same things as you do and is just looking to score. Stay away and when at work, just ignore him and ask that things be kept on a professional level.