OMG! That is awesome! That could work out great for this RP and I love all the old fairytales like the brothers grimm and all sorts of other old authors. I actually used an old fairytale for (Spolier for the post I just finished and posted) the red string in the dream thing I did. It is called the Red String of Fate. 
The two people connected by the red thread are destined lovers, regardless of place, time, or circumstances. This magical cord may stretch or tangle, but never break. It also can mean, destined to meet one another in a certain situation or help each other in a certain way