One day, an ordinary high school student is transferred to another world. He raises his level in the other world, successfully defeats the Demon King, and saves the world! With his strongest status, he decided to return to his own world; however, in the world to which he returns, a new "dungeon" has appeared.

Lee Joon was an ordinary high school student.

During the entrance ceremony, he was caught up in a strange phenomenon and died.

[You have died.] [Restarting from checkpoint.] [Loading…]

But then, a message appeared before his eyes.

『Congratulations on your acceptance at Nakseong Highschool, the school of secrets and mysteries. Uncover the shady secrets hidden within the school, or fight against the legends and ghost stories of the campus in order to earn points to unlock special abilities. Additionally, you must gather comrades to prevent the resurrection of the Demon King before graduation. The world is in your hands.』

A man who lost his family and fell into the depths of despair meets his end—only to be reborn in another world of swords and magic as Aldo, the heir of a noble family. He begins a new life alongside his twin brother Elphas and his loving parents. However, haunted by the fear of losing those he loves once again, Aldo starts to shut his heart off from his family. But when the roar of a ferocious magical beast threatens to devour them, the boy rises to his feet— determined this time to protect what he once lost in his previous life. A story of redemption and a second chance at heroism begins!

This shitty world that's nothing but a trashy game, he and I will definitely escape it together.

So, all these annoying women trying to take advantage of him are just a nuisance. What's worse, it seems like he's beginning to have some feelings for them.

That's why, for his sake, I'll eat them up first.

But, just what is this power...?

From MangaHelpers :
High school student Misumi Makoto is called into a fantasy world by the god Tsukuyomi, in order to be a hero. However, powerful others in this world aren't as thrilled to have him there, and they kick him to the edge of the world just as Tsukuyomi declares that he must leave Makoto to find his own way. Now it's up to Makoto to find his own way.

Da-in, ended up possessing the villain of a story.

To make Stardust — the story's protagonist and his favorite character in a dystopian manga — happy, he resolves to become the villain Egoistic for her growth.

Da-in deliberately causes terror to enhance Stardust's abilities and preemptively prevents all the tragic events from the original story, but in the process, he gains public support while also drawing Stardust's suspicion.

Stardust, who initially opposed him, gradually opens her heart, and soon even begins to show signs of obsession towards him...?

"I also wanted to be... the strongest in the world."

An Arch Mage who died without fulfilling his dream wakes up to finds himself being reincarnated as a member of the imperial family. And what's more is that his new body has a talent for close-quarters combat! This time he holds hope that he finally might be able to fulfill his desire of being world's strongest...

But after reincarnating his new name is Evangeline. Indeed, he had become a girl.
In her princess life where muscle training and fighting are forbidden, Eva brings dumbbells to her room and wields a sword! And before long, she becomes the strongest!?

A fantasy about a tomboy princess' rise to the top!

From MyPersonal-scan-: A remake and reimagining of the original series by Hara Tetsuo (Hokuto no Ken, Hana no Keiji) which ran from 1988-1989, with new art by Yoshihara Motoki. Cyber Blue: The Lost Children follows the story of Blue, a descendant of colonists from Terra who settled the distant world of Tinos in the 22nd Century. The brutal environment of Tinos forces humanity to rely on an artificial life support system implanted in the chest called the Biomatrix, in order to survive. In the 25th Century, Tinos is ruled by a Planetary Government bent on eradicating The Lost, dissidents who refuse to submit to its autocratic rule and are hunted down by its military for extermination. Through total control of Biomatrix production and issuing them to only those who submit to its authority, the Planetary Government enforces its will in an effort to finish off the Lost and their descendants, the Lost Children once and for all. Set in the dystopia of Junk City, Blue encounters Fats, a powerful robotic Artificial Intelligence, and the story of their meeting will change both man and machine, the fate of the Lost Children, and the course of human evolution forever.

When he came to his senses, Hirasawa Kazuki, a normal university student, found himself in possession of the body of a game’s character.

Moreover, it was Harold Stokes, the story’s most hated character who was even given the title 『King of tr*sh』by the players. Myriads of landmines are just waiting for him to step on them, like death flags!

Will Harold be able to clear the survival route while avoiding the countless death flags in his way?!

Artist's Twitter: https://twitter.com/_otsm_

The Star chef, KangHyun, hid in a quite countryside after losing his sense of taste where he found A pathway to another world in his grandfather's house. Since he was on the run anyway, he planned on enjoying a relaxing camp life, but... the people in the other world keep growing interested in KangHyun! Will KangHyun really be able to heal through experiencing a slow life?

In a far-off corner of another world where only nobles can use magic,
a certain thirty-something salaryman is reincarnated as a five-year-old village boy named Ren.

For him, the slow-paced countryside life is peaceful and enjoyable—
that is, until a group of adorable but terrifying little angels (a.k.a. troublemaking children) takes a liking to him.

Even though he just wants to be lazy, he ends up doing things perfectly—like playing hide-and-seek from morning till night, reading stories aloud, and calming their wailing cries—because he's just too good at taking care of others!

One day, while thinking of ways to slack off more, a monster suddenly attacks their once-peaceful village.
And when the problem children are put in danger, the usually unmotivated Ren unleashes a hidden power he's kept secret—just to avoid getting dragged into more trouble!

A laid-back reincarnated boy ends up babysitting (and saving the kingdom) in this reluctant hero’s tale!

In a world without cheats, a cultivation chronicle of wisdom and schemes. Among the students that were sent to another world were three childhood friends: Nao, Toya, and Haruka, who act to find equilibrium and create for themselves a peaceful place of living in the severe environment of a medieval-styled world. Whether it be mutual cooperation in monster subjugation or collection quests, there are no thoughts to become a hero.

Chimera hunter Number 17 has spent decades hunting monsters. On his latest mission, he’s ordered to ensure the human hunters’ escape and never return to base. In other words, he’s meant to die. As his body dissolves, his life flashes before him: kidnapped as a boy, forced into endless battles, reduced to a mindless weapon. But against all odds, his body reforms into his human form. No longer Chimera Hunter Number 17, he stands before a vast open land on his own two feet as Do-un Cheon, a human, ready to start his life anew, making friends out of monsters and building the family he never had.

Born as the Thirteenth Prince, Noah was originally in a position removed from the imperial succession, so he freely passed his time in the fief granted to him.

However, the Crown Prince died before the Emperor. The imperial succession would be fairly contested among the remaining princes.

Noah, being the strongest despite living freely, overwhelmed the other princes and eventually became the Emperor with the most power in the world.

Among the class transported to another world, Nagumo Hajime is an ordinary male student who didn't have ambition nor aspiration in life, and thus called "Incompetent" by his classmates.

The class was summoned to become heroes and save a country from destruction. Students of the class were blessed with cheat specifications and cool job class, however, it was not the case with Hajime, with his profession as a "Synergist," and his very mediocre stats.

"Synergist," to put it in another word, was just artisan class. Being the weakest, he then falls to the depth of the abyss when he and his classmates were exploring a dungeon. What did he find in the depth of the abyss, and can he survive?

Average high school student Mikagami​ Kouji is a hardcore gamer. One day he gets isekai'd and he only gets the skill "copy" which is apparently useless but we all know it's secretly OP or something. He's enslaved to be a gladiator by his summoner, the big booba, head priestess Zayd. He has to fight in the Colosseum and if he loses he gets raped.

She transmigrated as the opposing boss in the novel, but she was wiped out by the male lead. Fortunately, she reincarnates once more, but back to the past, when the male lead was still young! Looking at the pitifully weak male lead, she was troubled by a dilemma. Should she: 1. kill him, or 2. raise him up and openly ask for treasures from him. However, since she wants to get all sorts of treasures from the male lead, she chose the second option. Things don't always work out though, as she accidentally raises a sheep up to be a big bad wolf.

Master? Want treasure? Let's cultivate together, but alone, just us two, then.

The protagonist along with his step-mother, and 2 step-sisters are summoned into another world where demi-humans are the rulers as saviors, but its not to fight against a demon lord, its to fight an Undead Apocalypse monsters called "Dead Mell" that have overrun the world and that can only be killed by using weapons made with holy silver.

For that, a familia is made (group of 4 people) with them being the swordmaster that uses the holy sword, the guardian that uses the power of earth to protect, the healer that use the power of water to heal and the black mage that uses the power of fire to destroy.
The role of the guardian, the mage and the healer is to support the swordmaster that can only kill the monsters.

But to use magic powers one must offer part of your being as a sacrifice to form a contract with spirits, and the higher the sacrifice, the higher the power. Now they must choose who are the 3 that need to sacrifice part of their bodies to gain power and who will wield the holy sword.

After he and his entire class die on a field trip, Odamori accepts an offer from a mysterious man to be reincarnated. However his new job turns out to be that of a 'Slavemancer' with the power to dominate the minds of others and turn them into his toys, which he happily takes on. Soon however his evil actions lead to a Princess Knight (who turns out to be one of his previous, more popular classmates) being dispatched to apprehend him. But Odamori of course has something different planned for their reunion.

The story centers around the life of a young boxer named Ryuuji Takane and his sister Kiku, who is his coach. Ryuuji and his sister both inherited their father's talent for boxing with Ryuuji inheriting his strength and techniques while Kiku picked up his talent for analysis and strategy. In the past, their father was a famous boxer. Ryuuji and Kiku went away from home to train and become famous in order to help their lonely mother. On the way to stardom, they have to defeat the strongest challengers all over the world.