A conventional love story usually goes something like this: Boy meets girl, boy falls in love with girl, boy loses girl, boy wins girl back, they live happily ever after. An unconventional love story would be any love story that deviates from the norm, or that has a twist to it. Some examples of unconditional love stories told on film are Harold and Maude, Secretary, Fatal Attraction, Brokeback Mountain, or The Curious Case of Benjamin Button. Other examples would be stories about zombies or serial killers. If you need other examples or ideas, just google unconventional love stories. Good luck!