Well, he's got ideas besides watching a movie. If he is young than he's got bigger ideas, no offense. You got to set the guy straight and if it hurts well he will get over it..I could never imagine me asking a girl (woman) to watch a movie with me alone cause even to me that sounds kind of creepy.
Now to take a girl into public like a restaurant full of people that is little different..If you keep accepting flirty messages you're giving the guy wrong ideas. You need tell him look I don't mind being your friend but I am not into the dating scene and not looking for any guy at this time..The guy definitely has other ideas - so you need to really be on your guard.