In your story, have your two characters meet by chance. Perhaps your female character misses her bus or walks into a coffee shop just in time to meet her potential new lover. The two feel an immediate connection, but are pulled away from each other by circumstance. Find a way to help the two lovers overcome the obstacles standing in the way of their love.
In this story, the two lovers have known and been in love with each other for several years, but face ridicule and oppression from an outside force. Perhaps the two characters are of a different race, religion or social group and are forbidden from being romantically involved with anyone outside of that group. The story of the two lovers is similar to Romeo and Juliet, but with added twists. Find a way for these two lovers to be united, despite the barriers between them.
For this story, the two lovers are going on a wild adventure together. Through the story, infatuation turns into true love as the two fight off dangerous animals and survive perilous events together. Find a way for the lovers to become separated and reunited again.
Bring your two lovers closer together through a series of horrific or suspense-filled events. The two could be fighting off the supernatural, a psychotic nemesis or a deadly disease. Keep suspense high by threatening the well being of one of the lovers, only to have him or her escape the grips of almost certain death at the last moment.