His name is Theodore Greysmith. His family and friends used to call him Theo. He is a twenty-seven year old man who works as an office worker in a book publishing company.

This year is Theo's third year working at the company. Three years. Nine to five. Monday to Saturday. Theo had felt himself working like a robot.

He doesn't like to hang out with friends, meet with relatives, have a drink in a bar or find a woman. Instead of all that, Theo prefers to stay in his apartment, reading a book or just watching a movie while lying on the sofa.

Three years! His life is just leaving in the morning, working until evening, reading at night, then sleeping. On weekends, Theo spends watching television series or playing computer games.

So, Theo's life feels so monotonous. Even thought he bit enjoyed it. People around him don't understand what the joy of Theodore's daily life.

After more than three years of living like this. Theodore himself was starting to feel bored, but he still doesn't want to socialize.

Today, in the afternoon, as usual Theo came home from his office by car. On the way, his cell phone rang. His mother called, telling him to come home on Thanksgiving the day after tomorrow.

Theo made no promises that he would come. Pretending to be busy with work, even though it's just because he's lazy. Theo hung up the call.

Not long after, his cell phone rang again. Now he could see that his father's number was on the screen.

"Sigh…"

Theo exhaled. Not pick it up, but just turn it off. He didn't want to meet his family. He's just pure lazy. Traveling on holidays, for him, is the same as throwing the holiday away.

Until the apocalypse happened. Theo wouldn't want to leave his house. Holidays are precious days. A day where he could sleep as much as he wanted and empty his mind of worldly problems.

Arrived at the apartment. Theo put the jacket and bag in their place neatly. Putting his dead cell phone on the computer desk. Then go to the bathroom to wash off the sweat.

After showering and changing clothes. Theo made a cup of instant coffee. He loves coffee, but doesn't like making real coffee. Too time consuming. Instant coffee is fast, it only takes less than three minutes.

Taste is not important. Although he loves coffee, he is not a fanatic. As long as the taste is still good on the tongue, that's enough.

Theo brought the cup of coffee and a plate of mac & cheese to his computer desk. Turn it on and then immediately open the Redsquare site, a site for sharing videos.

While eating, Theo watched a video about a review of a new film series. He will always watch various reviews first before deciding whether to watch the film series or not.

In the middle of watching it. Suddenly his cell phone rang. From the tone, he knows it's giving a notification from the chat application.

Ignoring the cell phone. Theo's face remained glued to the computer screen. His mouth was still busy chewing. And his hands are still busy scrolling down the mouse, reading the responses in the comments section.

At the time after finishing reading one comment. Theo suddenly remembered.

'Didn't I turn off the phone?'

Glancing at the phone, the screen is still dark. Theo had some doubts about his ears earlier.

Is it possible for the phone to turn on by itself? Or had he just heard wrong?

Theo grabbed the phone with his left hand. Unlocked it, and sure enough. The phone has turned on with a notification displayed on the screen.

'Isekai Guide has been installed.'

"Huh? … what's this?"

Theo looked at the writing on the screen. His eyes weren't wrong. It is true that there is a notification of a new application. But… What is this application? Theo doesn't feel like he's ever downloaded let alone installed a new app.

He immediately opened the list of applications. View the most recent icon from a pile of previously existing icons.

The new icon has a castle illustration commonly seen in fantasy movies or cartoons. Theo squinted at the icon. His finger hovered over the icon, hesitant to touch and open it.

'Could this be a virus?'

The application installs by itself. Theo is afraid that a dangerous party will hack and send a virus to him.

'Isekai Guide?'

From the name of the application, Theo immediately remembered a fantasy trope that is currently popular in light novel circles.

Theo glanced at one of his bookshelves. The majority of his books are fiction and biographical novels.

History, computers, culture, manga and light novels make up only a small part of the entire shelf that surrounds every room in his apartment. In percentage terms, light novels are only about five percent of the total.

And the topic of isekai, you could say just a little. Theo was sure he had only read seven fictional titles with this trope. However, this was enough to give him insight into what is called isekai.

So… Theo looked back at his game icon. Usually isekai is a story in a fantasy world. If made into a game, then RPG is the genre that feels right.

Theo was quite interested in playing it. But, he is still skeptical. The presence of this application is too suspicious.

A few moments later. Theo felt his head burning at the thought of the suspicious app. Until finally he felt annoyed, and turned off the phone again. Then back to watching movie reviews.

Two days passed.

Thanksgiving Day arrived. Since this morning, his family has been calling Theo. He only received one call, namely from his sister. Said that he would not come and begged his sister to give an excuse to the family.

The rest of the calls were ignored. Theo silenced his phone, proceeding to tuck himself in the bed.

Theo got out of bed when it was time for lunch. He reached for his cell phone. Ordered a pizza to fill the stomach. After that, he saw the number of miss calls on the notification.

There are more than thirty calls. Theo just smiled at the number.

He stretched. Then go to the living room. Turn on the television, then start looking for the film series that from the review he's been watching last night.

About half an hour later. The doorbell rings. Theo jumped happily from the sofa, took his order, then went to the refrigerator, fetching two cans of beer. Then return to the living room.

At the time he wanted to continue watching the film. His eyes shifted to the cell phone screen.

There is a suspicious notification displayed on the screen.

"…Who is Rosalina?"

Theo take his cell phone with his left hand. Then take a slice of pizza with the right hand. While eating, he saw the origin of the notification which turned out to be from an application installed two days ago.

Theo became increasingly suspicious of the application. Thinking of the possibility of the application aims to spy into his daily lives.

"…Heh, impossible."

Theo laughed at the ridiculousness of his own thoughts. On his phone, Theo went to the memory settings section, looking through the list of apps and trying to uninstall the app.

Unfortunately, he tried many times. The process always fails. This makes it even more certain that the application is a virus.

Theo looked for the application icon named Isekai Guide again. Staring at it intensely while his mouth was busy chewing on the tuna pizza.

Touch.

Curiosity eventually overtook laziness and fear. The application that he had been ignoring for two days, finally opened.

A simple menu screen with a pitch-dark looking palace appeared. Theo tapped 'enter'.

At first. he thought that it would proceed to the login menu. But in fact it is not. The next screen instead immediately shows a kind of brief introduction to the story.

After ten years of surviving in Etheria. The goddess Venus gave a gift to Rosalina as a result of her hard work.

The gift that the Goddess gave was a system.

Young Man! Be a system for Rosalina! Lead this transmigration victim to behead the Demon Lord, so that she can return to her original world!>