Apocalypse: My Sweetie Is Tough but Cute - Chapter 727: The Heart Can’t Help but Tighten

Check in in front of Shicun Liushen, and get the reward Innate Saint Dao Embryo.

Check in in the False God Realm, and get a bonus cross-border amulet, which can be used to randomly enter other worlds.

Check in at Tianshen Academy, get rewarded with the secret of writing, the speed breaks through the limit of the world, and evolves time.

Check in in Xianyu, and get rewards.

After entering the perfect world, Shi Zhong got the check-in system and became a member of Shi Village.

Since then, the Eight Realms of the Lower Realm, the Three Thousand Dao States, the Nine Heavens and Ten Lands, the Immortal Realm and the Sea of ​​Heaven, etc., have all left footprints of stone bells.

- Description from novelbuddy

Kota Sakamoto—virgin weeb, social reject, and hentai game addict—gets sucked into a perverted dungeon world straight out of Carnal Labyrinth EX, the 18+ erotic strategy game he secretly 100%-cleared.The catch?All eight of his hot classmates and their strict MILF teacher got dragged in with him.The other catch?They hate his guts.Worse still, this dungeon world is exactly like the game—every level a twisted, orgasm-fueled survival puzzle where failure means death by overstimulation, lust-monsters, or trap-triggered climaxes that literally drain your soul.He’s the only one who knows how to survive.They either listen to the virgin... or moan themselves to death.Bondage plants, lewd slime traps, fetish trials, and orgasm boss fights await—and the only way forward is obedience.What starts as reluctant cooperation turns into obsession, as each girl slowly falls for the boy they once mocked...…the virgin who’s now their dungeon master.

A scientific genius named Thomas Harrier was transmigrated to an imperial prince body after a car accident that took his life. He found out that he is in a world similar to our own with a timeline akin to early twentieth century. The body that he is occupying was the imperial prince of a failing empire who suddenly rose to power after a successful assassination attempt of his father. Unaware that the attack is just the beginning of what is to come. He faces many challenges throughout. Will Thomas Harrier be able to live his second life in peace while running an empire and getting it back to its former glory? Or will he succumb into a conspiracy lurking within the country's borders?

Expect some:

Cold war era techs.

Super battleship with advanced electronics, propulsion, and fire control systems?
Helicopters?
Missiles?
Modern medicines and equipment?
AC-130?
A nuke?
Challenger or Abrams or Leopard?
F-4 Phantom or MIG-21?
Colored TV's.

Everything!!!

PS. Cover not mine, I just found it on google.

Haruto Hayase was a normal high school boy in his third year, living a quiet life until his younger sister, Haruka Hayase, joined the same school. Haruka’s beauty and charm made her the center of attention, quickly becoming the school’s prima donna. But when a notorious gang leader set his sights on her, he did everything in his power to protect her—only to fail tragically. Haruka was brutally assaulted and tortured, and Haruto himself suffered an agonizing death. However, in a twist of fate, Haruto is given a second chance, waking up a year before the events that shattered his life. Armed with the mysterious ‘Debauchery System Slave’, he vows to exact revenge on those responsible. This time, he will use his newfound powers of the system and charm to seduce the loved ones of his enemies. From their mothers, sisters, and lovers to their closest friends, Haruto will make them his. His enemies will suffer as he steals what they hold dearest, ensuring their downfall in the most devastating way possible.