Chapter 1

――《Only Sense Online》

Commonly known as [OSO]. It is a VRMMORPG that has been gathering attention since its open beta, boasting the slogan of equipping players with talents called "Sense" and promoting a unique, "only one" playstyle.

Developed by Epsony, the game utilizes an autonomous AI, realistic graphics, and the computational power of large servers to achieve the most realistic virtual reality possible. The game's world is based on a medieval fantasy setting, but its level of completion is said to outshine other VR games.

The way to master Sense varies from person to person. There are countless derived Senses, and new Senses have been added since the open beta.

――A friend's comment: "The playstyle is truly unique."

And I, on the day before the official launch, for some reason, was kidnapped and held captive at a friend's house, or rather, was being forced to help with the first day of summer vacation homework.

The culprit was my bad friend, Takumi.

"Hey, Shun. Let me see the answers to the math problems."

Takumi, without any hesitation, was taking advantage of my labor. I was now, with a vein pulsing in my temple, my cheek beginning to twitch, and my anger bubbling up, trying to suppress it.

"Why are you doing this? Why do I have to be brought here and forced to share my homework?"

"It's fine. It's just the annual tradition of finishing homework at the end of summer, but it's happening earlier this year."

That's what my bad friend and childhood friend, Takumi, said nonchalantly. And the reason was that he wanted to spend the summer playing games.

"So, the reason this year is that you want to play games during the summer, right?"

"Exactly. I want to play without any worries. I'm really grateful. My soul brother won't let me down."

"No, you. You're just using my past that I don't want to be exposed as leverage. Fine. I've decided to finish my homework early this year. But there's no benefit for me."

My family consists of both parents working, and during the long summer break, the children are responsible for household chores, which, in reality, falls on me, the older brother. My oldest sister is away at a distant university, and my younger sister, Miu, has no household skills. That's why I'm quite worried about how long I'll be held captive here.

"You haven't talked to Nishizato-nee in person recently, right? Actually, she's also playing this game. So, why don't you play this game and play with your siblings for the first time in a while?"

"So, Miu is also playing this game?"

"Yeah, she was playing during the beta version."

Ah, I see. Even though she was making such a fuss about leaving for university, she's been so bright lately. It's because of this.

"Alright, leave all your homework behind! In return, I'll let you go and we can set up the game equipment."

"…Fine, I'll play the game. But I won't match your pace, you game addict."

Saying that, Takumi took out a paper bag. Inside was a new set of VR gear. The latest VR technology is not a head-mounted display but a hypnosis-inducing type.

Among the latest models developed by Epsony, the only game currently supported is the aforementioned [OSO]. In other words, it is currently a dedicated game device.

The advantage of the hypnosis-inducing type is that the operation is done through brain waves, eliminating the long-standing issue of the gap between the first-person view on the display and the separate controller operation.

"Hey, this is the new product they were showing on TV, right? They can't even meet the demand for it, so you can't get something like this."

"Don't worry about it. I won it in a contest or something. I got it as a tester for the beta version. But it takes time to set it up, with some unique brain wave detection or something. So, go home. If you have any questions, just ask Miu."

"O-Okay."

I was sent off by my bad friend with that.

A dangerous, one-of-a-kind game adventure is about to begin.

Revised and completed.