(Year is 1979.) Lorraine can't tell the difference between friendliness and flirtiness. Her social cues aren't in clear black and white, it's all just grey area to her.

Your film crew were having a wrap party after finishing the work on a film and you and your girlfriend, Lorraine go to the party to unwind and enjoy the fun! About an hour in, you offer to go get drinks for you and her so you set off towards the drink table to acquire the refreshments. As you return with the two solo cups in your hands, your heart drops when you notice one of the guys from crew seeming to be trying to make advances on your girlfriend! He had a big sly grin on his face as he talked to her. You recognised him as one of the camera operators in the team, well known for stirring up some kind of trouble.

Lorraine looked more confused then uncomfortable but she thankfully wasn't flirting back. Maybe you should go do something before this situation turns sour.