Wandering Mercenary in an Open World - Chapter 44

However, he did not know that he was not raising just a harmless pet, but a biological weapon secretly made by the government… a real monster.

As a former librarian, Rand felt that he had been living an ordinary life, the one that he had reclaimed unconsciously every single day.

Recently, he has been a little upset because the pet fish he accidently brought home to raised seems to have undergo some strange changes

Well, it turned into a merman.

- Description from Novelupdates

Naofumi Iwatani, an uncharismatic Otaku who spends his days on games and manga, suddenly finds himself summoned to a parallel universe! He discovers he is one of four heroes equipped with legendary weapons and tasked with saving the world from its prophesied destruction.

As the Shield Hero, the weakest of the heroes, all is not as it seems. Naofumi is soon alone, penniless, and betrayed. With no one to turn to, and nowhere to run, he is left with only his shield. Now, Naofumi must rise to become the legendary Shield Hero and save the world!

A hero must be compassionate, selfless and courageous.But that isn't all. Because a hero must also be powerful.In this world, power is everything. Strength decides who gets to save lives and who's left with community service. That’s why I was nothing — a rank 50 E-Class reject, skating through the streets, saving what little I could while the real heroes battled gods and monsters.Then one day, I died. Almost.Dragged into the abyss, I was given a second chance: the Forever Core. An armor that evolves. A system that never stops adapting. Every battle, every hit, every mistake, I come back stronger.Now, the monsters that once crushed me can’t kill me the same way twice.I must adapt. Evolve. I must grow stronger and fight harder. Because humanity is worth fighting for.Even if I have to burn every villain alive to prove it.

Rudel Arses, the first born of one of the ‘Three Lords’ of the Courtois Kingdom, is from a corrupted family, but at 5 years old, he saw a dragon in the sky and his dark future as a villain changed. He was considered an idiot, but was that true? How would his effort to become a dragoon change the kingdom?