The movie is about a demon and her lover, an angel that was missioned to hunt and kill her. The movie starts with them chaseing each other through space and then cuts to a young girl that has been set up on a blind date. The demon crashes the party by possessing the girl. Ends up killing the guys at the party but the angel tracks her and crash the party too. There is a little bit of cat and mouse and then after causing a lot of damage they set chase again leaving the party. I hope someone can help me. I have been going nuts trying to find it. It's a comedy from the 80's I think.