This happened last summer. I had just started walking for exercise because I'd gotten self-conscious about my waistline. Given my job, I was busy from midday until around nine at night, so I decided to walk either early in the morning or late at night. But I could never beat the morning sleepiness, so I always ended up going out late at night for about an hour.

Listening to songs I used to love back in my student days while walking down empty streets with hardly any cars or pedestrians actually felt pretty good. After a few months went by, the heat wouldn't die down even late into the night, and I was sweating more than usual every day. Deep down, I thought, 'I'm sweating a ton and sticking to a disciplined routine, so I must have made some progress by now...'

Yet, I had gained weight. My weight had gone up so much that I wondered if the scale was broken; it made no sense at all. I brought up my weight gain to my coworkers as a funny story, and most of them laughed. But there was one person who didn't laugh, keeping a dead serious expression on her face.

Let's call her Ms. A. I asked her, 'What's wrong?' Still wearing that grave expression, Ms. A whispered, 'I think the reason you're gaining weight is because of the woman standing behind you.' I blew it off with a laugh, assuming she was just joking. I would soon regret not listening to her.

Things shifted when the funny story I told my coworkers reached my department head. He came to me with a deal: 'If you record a video of yourself walking and manage to lose even one kilogram in three days, I'll give you a cash bonus.' Of course, I knew he just wanted everyone to watch me walk around and have a good laugh. But lured in by the promise of extra cash, I readily agreed.

Never imagining what terrifying footage would actually be caught...

Starting the night I spoke with my boss, I walked much farther than usual. To make extra sure, I increased my strength training reps and sweat it out in the sauna. Finally, from the night of the second day until the moment I weighed myself, I didn't eat a single thing. I thought, 'After going this far, there's no way I haven't lost weight.'

Work ended, and the time came for the weigh-in. Since I'd exercised and practically fasted, I was sure I'd shed some pounds. Still, facing the scale made me a little nervous. I stepped onto it slowly, and to my shock... I had gained eleven pounds.

Everyone, including my boss, burst out laughing. But just like before, Ms. A didn't laugh. My boss said, 'Let's see that walking video,' practically assuming I hadn't gone walking at all. Feeling a bit annoyed, I connected my phone to the office TV and played the video of my walk.

Everyone was impressed, agreeing, 'You really were walking.' But then one coworker noticed something strange: 'Isn't the video runtime way too long?' I answered, 'Maybe because I walked longer than usual?' But the timer showed it was over six hours long. Except for Ms. A, everyone assumed I'd just forgotten to stop recording. Curious, we all decided to fast-forward to the last five minutes.

For about two hours, it was footage of me walking. After that, it showed me coming home, going to take a shower, and eating a salad—just my normal routine. Shortly after, it showed me turning off the lights and going to bed. But around the time I fell asleep, footage played that no one could have anticipated.

The room went dead silent as we watched footage of me slowly getting up toward morning, opening the refrigerator, and devouring food. My eyes were closed, and my mouth was open impossibly wide as I shoved food down my throat. I looked like someone completely possessed.

Since I lived with my parents, the fridge was always well-stocked. But I couldn't believe I had been binge-eating in my sleep. Just as the video was coming to an end, everyone screamed. A woman's figure appeared, overlapping right on top of me.

She was on screen for only about two seconds. But she was clear as day. She was unmistakably fused with me. Staring at the TV screen, Ms. A muttered, 'See? I told you so.'

The next day, I rushed to a temple to get an exorcism performed. Without me explaining a single detail, the monk told me, 'You are possessed by a woman who suffered from starvation during the war.' A chill ran straight down my spine.