In any city, in any country, go to any construction site or foundry you can get yourself to. When you reach the front desk, ask to visit someone who calls himself "The Holder of Twins". A person will suddenly appear beside you and the worker will be gone. Ask the person the same thing, but the answer will be that the worker is currently away, talking to his boss. He will tell you that both of you will have to wait until the worker comes back.
In that very second, the worker will reappear, seemingly out of nowhere. He will politely ask the other person to wait while he tells you that you may follow him. Do that and ignore the other person disobeying the worker and be glad that he didn't obey, or you would have walked into your death.
After a short while, you will reach a paper door. But do not let it fool you; this paper is stronger than any metal you have ever seen. The worker will now open the door, letting you in. The other person will quickly follow you. If he doesn't, pray for a swift death.
Should he have followed, both of you will find yourselves in a small paradise. Although you will find everything you like and love in this place, do not touch anything with your hands and arms, for the beauty will then quickly fade away and madness will overcome your mind. Simply follow the path you see below your feet and never leave it.
The other person will do the same, and you will have to talk. Tell him about everything you can remember from your life and hope that he doesn't talk back. Neither you nor he want to know what will happen if you ever stop walking while being on this path. For hours, you will walk and you will have to keep talking all the time. Finally, as you see something shiny at the horizon, you may complain about a sore throat and that you have nothing else to talk about.
You will reach a golden door. The closer you come, the wider it will open all by its own. Enter the door and you will find yourself in an almost pitch-black room lit by only two candles. One of them is beside a mirror, the other beside a rucksack. Walk to the mirror and stare into it, as horrifying as the pictures may be. You will notice the other person walking towards you; your fate will be decided in the next moments.
Should he scream, "No matter how hard the work, it will be done!" and then smash the mirror, then your fate is sealed. After he has destroyed the reflecting item, you will feel unbearable pain and you will scream, out of instinct. You will be melting in the next seconds. The other's task will be fulfilled.
But, should he choose to do nothing, you may utter the question, "What reflects them?" You will now see the other person slowly melting and he will scream inhumanly. Endure the screams for about a minute, then he will be gone; only the rucksack he has worn will be left. Open it, take the mirror inside it and you will be returned to your home.
The reflection is Object 60 of 538. Don't ever dare to destroy it.