This is set in modern day, pretty much everything about this world is the same except for one thing. Somehow a version the unbreakable vow from the harry potter universe has made its way to the normal world. There are some rules around the vow. It can't be forced by a threat. It has to be a true agreement. When the vow is made correctly it is unbreakable. If you break it, you will instantly die and this is a well known fact. Obviously we are all raised from a young age to know that they may never break the bond.

You are a on a trip with some friends from college up in the mountains and you decide that it might be fun to go hiking and explore a local cave. That ended up being a horrible mistake. At first everything was fine and there was a pretty clear trail. Then you hear a pattering on the roof and realize it is raining. The. You hear the water rush in. In a panic you run up into an area you aren't familiar with and lose your friends. What you didn't realize is that many if these chambers contain dangerous buildups of carbon monoxide. You panic and pass out and wake up some time later. You know you have to escape. You run jtni you girlfriend who is having the same problem as you. You are both desperate. Hours pass and you are feeling trapped and hopeless. Suddenly your friend passes out again. No doubt from carbon monoxide. You try to drag her to safety but you aren't sure you are strong enough to.

Suddenly you see a light approaching. I have arrived with a wetsuit and an extra oxygen. You feel relieved. But I am an opportunist. I know this area and the cave well and I saw your vehicle and assumed you were lost. I tell you that I know my way around the cave and I will save the lives of both you and your friend. One catch. You need to make an unbreakable vow to return to me in several months to live the rest of your life as my slave, you can tell nobody about the arrangement. If you ever run away or leave without my permission you will instantly die according to the vow. You know in your heart that the vow will probably work and you wouldn't want to test it. I am not putting a fun tinyiur head, this is basically a good deal for you tinsave yourself and your friend. I give you and your passes out friend a little oxygen and food and give you some time to think about it. You know that you really don't have a choice. You are going to have to submit to this total stranger for life to save yoursekd and your friend. Your fiance is probably going to be so upset.

Maybe you can haggle with me a bit jver the details? Maybe you can plead? You can try but it may not be worth it. I could just leave you to your fate.
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