Omniscient Reader’s Viewpoint (Web Novel KR) - Chapter 448: 1864 (4)

Wang Yi gets a key, opening a door in 2022 will lead to 1982, and opening a door in 1982 will return to 2022.

Two very different great eras appeared before him:

Abundant dietary protection, developed industrial products, miraculous medicines, and explosive information, this is 2022.

Simple folk customs, rich wild resources, scattered antiques, and treasures of the age, this is 1982.

Traveling between these two eras, Wang Yi didn’t think much of it, he just wanted to live a good life.

- Description from novelbuddy

“Everyone deserves a happy ending, don’t they?”…In the brutal fantasy RPG Fall of Ares, saving the world came at a cruel price — the deaths of every heroine the player had grown to love. No matter how skilled you were, their sacrifices were inevitable. The game warned you not to get attached.But one young man did.After beating the game and lamenting their tragic fates, he wakes up in its world — reborn as an extra, armed with one mission from a mysterious system:[Change their endings. Let them live.]Now enrolled at Mysteria Academy alongside the heroines doomed to die, he must rewrite fate itself. For every girl he saves, he’s rewarded. But the world resists change. Calamities draw closer. The true enemy — the Children of the Sky — are watching.And one of the heroines… remembers it all.

A novel revolving around being transported to another world with an op system. The mc spends his day chasing skirts and doing missions to level up. A standard journey to the top with lots of girls from various animes and games with a twist of that gaming feel (hunting mobs, doing missions).

- Description from novelupdates

Maid, older sister, younger sister, and even mother, all of them.