I've got a Succubus for a Girlfriend - Chapter 2: Damn it

Within the virtual world of “Avalon Online”, Finn, or otherwise known as “Echo” within the game, was one of its greatest players. After logging off from a long session, however, he notices something awry outside of his apartment.The streets were flooded with chaos, screams echo through the night, and hell is loot loose. Monsters from Avalon Online are running through the streets, wrecking havoc. In the midst of this hellish awakening, Finn is greeted with the one gift bestowed to humanity in this dark hour:[...Assessing life experience…][Assessment Complete][Name: Finn Thorne][Age: 20][Designated Class: Assassin][Starting Level: 5][A [Legacy System] has been bestowed to you for your accomplishments within Avalon.][Assimilation System Awakened.]In this twisted turn, as the world as it was once known is gone with the arrival of magic and monsters, the remnants of humanity must level up if they wish to survive.Finn is left in this dark, hopeless apocalypse, using his own experience from Avalon Online to best survive what seems to be an impossible task.

What does it feel like when you have a best-selling detective fiction author for a boyfriend?

Whenever you offend him, he would look at you disdainfully, “A character molded after you could only ever appear in my novel as a deceased victim.”

Whenever you seriously offend him, he would threaten you, “The very next victim who dies in my novel would be named after you.”

Whenever you seriously, seriously offend him, he would add on to the previous threats, “Furthermore, the victim would have died at the hands of an extremely perverse and twisted serial killer, and would have suffered an extremely painful and terrible death.”

But, by a stroke of coincidence, if you happen to be this best-selling author’s editor, he need not resort to the above mentioned tactics. In fact, all he has to do is one, single thing –
-Delay the submission of his draft.

- Description from Novelupdates

The world has turned into a hell, a place where the strong thrive!

Kōdo Ikusei Senior High School, a leading prestigious school with state-of-the-art facilities where nearly 100% of students go on to university or find employment. The students there have the freedom to wear any hairstyle and bring any personal effects they desire. Kōdo Ikusei is a paradise-like school, but the truth is that only the most superior of students receive favorable treatment.

The protagonist Kiyotaka Ayanokōji is a student of D-class, which is where the school dumps its “inferior” students in order to ridicule them. For a certain reason, Kiyotaka was careless on his entrance examination, and was put in D-class. After meeting Suzune Horikita and Kikyō Kushida, two other students in his class, Kiyotaka’s situation begins to change.