Using entries to cultivate immortality in chaotic times - Chapter 420 - 173: "One must use their own life to uphold the teacher’s prestige."_3

Perhaps it is the choice of fate. As a senior otaku, Qian Lingfeng got the “steel shell system”. However, when he swept the world with the system, became a local rich man, made all kinds of beautiful women, opened a harem, and realized the ultimate fantasy of thousands of otaku, he found that things seemed far from simple!
When the end comes, biochemical zombies suddenly come down, fierce beasts are in power, bloodthirsty zerg roam to kill the world, and human lives are comparable to dirt. Where will weak human beings go in this world? Is humanity going to be extinct? Or … can an otaku save the fate of the human race?

- Description from Novelupdates

Athen had always lived a solitary life, as without any family or friends, he struggled to survive in his poor, forgotten hometown. The only escape from this grim reality came in the form of tales of magic told by rare visitors from the distant capital.That was, until one day, Athen discovered that magic wasn't just a dream. It was within him.With his newfound power, Athen completed a desperate heist, stealing a priceless diamond. But his triumph was short-lived when he realized the diamond was a fake.Yet... what seemed like a cruel trick turned out to be a blessing in disguise, for the fake diamond held the key to unlocking Athen’s greatest desire: the chance to truly learn magic.

Crossing to One Piece world, he became Roger’s younger brother.

Unexpectedly, Gol-D-Roger who was in his fifties had a teenage brother. But he was so weak.

Fortunately, at the age of sixteen, he actually found himself with a possession soul system.

He had attached to the master IP man, also to the White Phoenix and to Ge Nie with his strong ability of the Hundred Step Flying Sword.

If you think that he can only Purchase these? Then you’re wrong!

Pain, Itachi, Ichigo Kurosaki, as long as there is money, any soul can be Purchased.

- Description from Novelupdates

This is an Isekai styled story, written from the point of view of the protagonist.

Discover the secret of the new, unknown world with Peter, as he sets his first steps in an empty, ruined city. Meet new people from all around the globe. Fight, laugh, and cry.