This Text Adventure Game is definitely poisonous - Chapter 8 - Explosive Sales Volume_1

Eren Idril died as an old, decrepit, and piss-poor adventurer by the maws of a D-Rank monster. He had a lot of unfulfilled dreams and desires that couldn't see the light of the day after the light in his own eyes died down.

But fortunately for him and unfortunately for the world, that wasn't his end. Eren was somehow dived back in time when he was a mere teen, attending Lionheart Academy for adventurers.

When life gives him a second chance, Eren decides to exploit it to its fullest. Experience his vile deeds as he partakes in them without feeling the slightest bit of hesitation.

Su Ran, a music prodigy, woke up transmigrated into a book.

At that point in time, the main story arc in the book had already been completed. As a villainess female supporting character, not only did she need to take over the original owner’s pitiful life in poverty, she also gained an instant son right at his rebellious period.

Ten or so more years from then, the son would turn into a twisted, evil villain. He would appear in one of the extra chapters to pick on the male and female lead’s children.

***

Su Ran: Son, you shouldn’t be too outstanding.
Su Han: Why not?
Su Ran: ’cause you will be killed.

Su Ran: Son, would you like to learn music from me and become a zen, little fairy boy who only needs to drink dew.
Su Han: No, I want to go into business so I can support you.

- Description from Novelupdates

Have you ever seen exposing holy vein?

“Teacher, you know me. I’m usually a good student, with nearly 100% attendance, and I’m also eager to help the people.

Yesterday I flew to the coast to fight monsters, so…”

“Teacher, you know me. Which teacher is not full of praise for me, but things are prioritized. Yesterday happened to be the Ghost Festival. Hundreds of ghosts walk at night, so I…”

“Teacher, you know me well. I am an activist in our dormitory. Every day I call them to go to class, but under special circumstances, so…”

“Teacher, I’m a foreigner, I don’t understand what Xie said, and I didn’t know there was a class yesterday, so…”

The teacher took off his glasses and rubbed his temples, “I can tell that everyone in your dormitory has stunts, but this is by no means a reason to skip class! This class! This year! You guys are all done!”

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Another version of the introduction: Ultraman Delta was living in another world for unknown reasons. Originally, he wanted to be an ordinary college student, waiting for one day to find a way to return home.

But the sudden appearance of a monster disrupted his plans, and he also discovered that his roommates were not ordinary people either.

- Description from novelbuddy