MTL - Comprehensive Manga: a Journey Through the Supreme Being - Chapter 76

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

Bai Fan was a Chinese medical university student who woke up as a Japanese high school student named Kitagawa Tera about half a month ago.It was just like a typical starting point in a novel. He re-experienced life as a high school student in his twenties. Youthful, energetic girls, and colorful love comedies…That should have been the original plot…However, heaven was obviously playing a joke on Bai Fan as he had not inherited any memories of the original Kitagawa Tera.Follow the level-headed and cold Kitagawa Teru as he navigated around his new world with the ‘System’ that constantly gave him supernatural quests to clear.

The whole world mutated. Mysterious resurrections happened in real life. The Tribulation descended.

When a fantasy kingdom needs heroes, they skip the high schoolers and summon hardened Delta Force operators.Lieutenant Cole Mercer and his team are no strangers to sacrifice. After all, what are four men compared to millions of lives saved from a nuclear disaster? But as they make their last stand against insurgents, they’re unexpectedly pulled into another world—one on the brink of a demonic incursion.Thrust into Tenria's realm of magic and steam engines, Cole discovers a power beyond anything he'd imagined: magic—a way to finally win without sacrifice, a power fantasy made real by ancient mana and perfected by modern science.But his new world might not be so different from the old one, and the stakes remain the same: there are people who depend on him more than ever; people he might not be able to save. Cole and his team are but men, facing unimaginable odds. Even so, they may yet prove history's truth: that, at their core, the greatest heroes are always just human.