Okay, this is my first attempt at this, so be gentle :)
An idea that I have wanted to RP out (and this doesn't have to be these lines exactly, but the idea of it) would take place in an old world setting, you being a nobleman, me being from a noble family as well, but much less affluent. My family would be in debt to yours and rather than lose face and land, they sell the youngest daughter (somewhere between 18-22ish) to your family.
Possibly for marriage (still from a good family name) possibly as a servant, but she's willful, and wont accept the new situation easily.
Okay, that's probably more detailed than this should/needs to be, but there is :)