(Y/N) Zoldyck is from the family of famous assassins, your training was done and now you're one of the best assassins in the world, (Y/N) is sick of killing for her your family and money, so when you are 12-ish (turning 13), you got on to the last b...
Bill lead you inside the treehouse to see what he did with the place, you only thought of the design of it but didn't think to as far as what to put inside.
You thought that you would have a hard time making the treehouse, but it turns out that Bill helped made it for you.
You and Bill arrived at the porch, Bill stopped at the door and turned to you. "(Y/N), this door has a lock on it and this is the key to unlocking it." Bill handed you a key.
[choose one of the above keys, if they are not to your liking then you can think of your own, at long as it's a key and it could be a necklace.]
You took a good look at it. "Are you serious? This key could be easily copied by others. It's so simple."
"Ah, but that is what I want others to think when they see it. This key would only unlock this door if the one who uses it is you, (Y/N). If it's not, then that person would be poisoned." Bill explained.
"What if you used it." you pointed the key at him.
"I wouldn't die! The key would just take my energy for as long as I hold it." Bill laughed. "Go on, unlock the door to your treehouse." Bill moved away move the door and let you through.
You placed the key inside the keyhole and turned, you can hear the clink sound of the door being unlocked. You looked at Bill and he nodded meaning for you to go on in, you nodded back and went in after taking the key out.
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When you got in you fell on your knees, literally. Bill walked past you and sat on the brown chair, and asked, "Is this not to your liking?"
"What?" you got pulled back from your daydream. "No I'm just... wow..."
"Turn around." Bill said and pointed behind you. You got up and turned around.
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"Wow..." was the only thing you could say at the time.
"The glass door closest to the staircase is the one leading to the porch, but a bigger one. The other plain wooden door without any window is the one we used to come in." Bill explained. "The glass door also needs to be unlocked from the outside with the key I gave you, but you can open it from the inside as well."
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