Reincarnated as an Apocalyptic Catalyst - Chapter 88: Stranger at the Door

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.

Arthur was a weak and cowardly boy who lacked the power to protect anyone—a truth brutally demonstrated when his parents were massacred while defending him during a Gate outbreak. As the sole survivor, Arthur spent weeks believing his life was over. When intense chest pains began, he assumed he'd been infected with corruption by the void creature that killed his parents and was merely waiting for death.What Arthur didn't expect was that these sensations actually signaled his Realm Core forming. In two months' time, he would be forcefully transported to the next realm and awaken new powers, becoming one of the world-renowned “Chosen” who protect humanity from Gate outbreaks. Now Arthur must rise through the heights of power, climbing each of the seven realms in hopes of saving his world... or does he?

Back in 1998, an ordinary person who has been through, tired, cried, and fought, hopes to run down-to-earth and keep up with the trend of the times.

- Description from novelbuddy

Ryo Tanaka, a struggling college student, works tirelessly at multiple part-time jobs to make ends meet. In a bid to earn some extra cash, he volunteers for a paid drug research study, unaware that it will alter the course of his life forever.The experiment takes a disastrous turn, leaving Ryo bedridden with a high fever for several days. But when he finally awakens, he finds himself in a world plunged into chaos. A deadly virus has ravaged the city, turning its inhabitants into ravenous, flesh-eating zombies. Streets once bustling with life now lay desolate, the remnants of civilization crumbling under the weight of the apocalypse.