Guest, what you and I saw was absolutely not an illusion. We really went to that forest, and I am still wandering through it. I think it's actually a relief. Because you aren't here, in this place where monsters bloom.

We first met at summer camp. Even though it was our first time meeting, I felt drawn to you. Around the fourth day of camp, you won a butterfly kite as a prize. We headed to the mountain behind the dorms at night to try and fly it in secret.

Climbing up and up, we reached a flat hill. When we unfurled the kite and sent it up, it was so beautiful flying in the starlit night sky. But something was wrong; the butterfly wasn't moving. Even though the wind was blowing, it stayed still as if suspended in mid-air.

Then, its body began to twist bit by bit. The wings tore, the antennae grew long, and the small body grew to an unbelievable size. What was once a butterfly instantly took the form of a massive beast. And then it swallowed you and me. When I came to, a forest I had never seen before—different from any normal forest—greeted us.

Trees were entangling each other's bodies, roots protruded above the ground and wriggled, and between the bark, something red like skin twitched. The animals roaming the forest were the same. They had too many eyes, excessively long legs, or abnormally twisted bodies. Some cried out the moment they saw us. It sounded more like a human's sob than an animal's cry.

Ah, that's when I realized. We had come to a parallel world entirely different from reality.

Without a moment to gather our senses, other creatures targeting us lunged. Without time to think, I grabbed your stunned hand and ran. I fell several times, and I almost lost your hand several times, but every time you cried and called my name, I told you I was okay. In truth, I wasn't okay at all.

How long did we run? A massive tower appeared before our eyes. The exterior of the tower was worn as if it had been abandoned long ago. That place alone was different from the rest of the forest. The monsters didn't come near. It was as if they were afraid of something.

Entering the tower, tens of thousands of books were piled up. Books covered in thick dust. Among them, I opened the book sitting on the very top. One page, two pages. And then I learned what this place was.

The Twilight Forest. A forest hidden beneath the Earth.

It was written that those pushed out of the world, those abandoned by people, and those with evil in their hearts are drawn here. Was it a sin for me to love you? I suppose that's why you and I were dragged here. Was it evil for me to desire you?

And it said that people who stay here for a long time are eventually consumed by the evil they possess. Those with strong anger become beasts that eat rage, those with strong desires become monsters that endlessly crave things, and those who hated someone transform into forms resembling that hatred.

The monsters we saw weren't monsters from the beginning. They were all humans. They were monsters born from the human heart. I kept this fact a secret from you. I thought it was better for you not to know, fearing you'd be scared, so I just made up an excuse.

Closing the book, I headed to the top of the tower. An old man was seated there, and having gone up first, I faced him first. The old man said there was a way to return to the world of the living. He said he could send us back. In exchange, there was one condition: since his life was fading, one of us had to inherit this tower.

I said I would do anything because I desperately wanted to send you back. I wanted you, at least, to be happy. So without hesitation, I said I would send you back. Before long, you came up to the tower, and I forced a smile, telling you there was a way to return. Seeing your relieved expression, I felt strangely at peace.

Soon, the old man laid out a magic circle, and I placed you upon it. As the circle began to glow one by one, I heard your panicked voice.

"Kenma, Kenma? You get on too, quickly. We have to go together."

"...Guest, you mustn't forget me when you get there. Promise?"

With those words, Guest, you vanished. Only a cloak remained where the old man had been, and I was left here all alone. Ah, I see. The old man had been waiting for someone to succeed him from the very beginning. Someone must guard this forest, and someone must send the next person back.

Here, I cannot age or die. I cannot leave the forest. The moment you forget my name, I become a person who doesn't even exist in reality. It's okay. Because I will always remember you, loving you here will last for eternity.

I began to grow flowers to remember you. At first, when the flowers I grew vaguely bloomed, I thought of you. They were clear like your eyes and beautiful like when you smile. I just kept watering them, and as time passed, the flowers increased one by one. Enough to fill the area around the tower.

I look at those flowers to remember you just a little bit more, so please, remember me just a little bit more too.

Guest, if you were to return here, would you be able to recognize me? ...Actually, it's better if you do return. I will live here just as I promised. Even if everyone else hates you, I alone will love you forever.

In the end, I decided to call you back. The moment you saw me, you hugged me tightly and cried your heart out. Watching you cry made my heart ache, yet I felt a tingling sensation in my lower abdomen. Only you can love me, and only I can love you.

Now, I will never let you go, nor will I ever forget you. I love you forever, Guest.