Here we go, some more ideas!
Princess/Dragon - Same old story, a princess is captured by a dragon. But this time she doesn't get rescued. (The dragon would have a human form)
Maid/Master - A young maid is hired by a pervy master and gets harassed Hitchhiker/Driver - A runaway teen gets picked up by a stranger and doesn't just get a ride
Poor Girl/Rich Guy - A girl hates her classmate because he's a typical snobby rich guy. When he helps save her father's job (through his wealthy connections), she thinks he might not be so bad, but then he uses that against her to basically blackmail her into doing whatever he wants.
Teenager/Dog - Bear with me here. A girl gets a new dog, but little does she know that the dog is actually a very horny man stuck in a dog's body. He could either be a dog the whole time, which would mean beastiality, or he could be able to temporarily transform into a man.
Cheating Fiancee/Random Stranger - Only a few days before her wedding, a young woman starts having second thoughts and goes to a bar to try to calm her nerves with a few drinks. She ends up meeting a drop-dead gorgeous stranger and sleeps with him, and then neither of them can get each other out of their minds.
Grandfather/Granddaughter - Not very common, but I've been wanting to try something with a large age difference. A granddaughter comes to stay at her gradnfather's house in California for spring break, and he's been awfully lonely since his wife died.
Mermaid/Fisher - A mermaid gets caught in the net of a fisher who makes his living searching for rare creatures. Of course, he doesn't want to let her go... so he takes her home to add to his private rare fish collection (he is rich and practically has an aquarium in his house). Then he discovers that if she is left out of water long enough, her tail turns into legs.
Teenager/Internet Creeper - I've been wanting to play with another character who is very creepy. A girl makes friends with someone she thinks is her age and agrees to meet him, but then is kidnapped by this 'friend', who is an internet predator and is quite disturbed. Abducted Girl/Alien - Just what it seems like. An alien researcher abducts a girl for scientific research on humans. This could involve tentacles? Or not. Whichever you'd prefer.
For any more elaboration just ask ^_^
Feel free to take a peek at m ons and offs and see if you likey...