Totsuka Yukikazu was a student in the peaceful Japan, when suddenly during class break, he and his classmates were caught up in a summoning to another world. In the otherworld he got offered a position as an otherworldly warrior that would fight for the kingdom or the choice to take his freedom and walk his own path. With a mysterious voice in his head that told him to abandon the castle life, he decided to take his own path and become an adventurer!

... After he finishes his 2 year mandatory military service

Webnovel https://ncode.syosetu.com/n4944ff/

Iruma Takumi, a 40-year old salary man, was dragged into a hero summoning just like in a template. What was his fate? The Goddess sent him and the heroes to the other world separately.

With the Goddess’ overprotective support, he landed in a different world looking handsome, rejuvenated, and quite different from a Japanese.

Although he wanted a slow life while working in the manufacturing trade, that was not permitted by the Goddess’ special body and abilities.

Would Takumi be able to live a peaceful life in a different world?

From MangaHelpers:
29-year-old programmer Suzuki Ichirou finds himself transported into a fantasy RPG. Within the game, he's a 15-year-old named Satou. At first he thinks he's dreaming, but his experiences seem very real. Due to his use of a 3-time-use special power (meteor shower), he ends up wiping out an army of lizardmen and becoming very high level. He hides his level and plans to live peacefully and meet new people, though developments in the game story (like the return of a demon king) might get in his way.

In the prosperous kingdom of Pars lies the Royal Capital of Ecbatana, a city of splendor and wonder, ruled by the undefeated and fearsome King Andragoras. Arslan is the young and curious prince of Pars who, despite his best efforts, doesn't seem to have what it takes to be a proper king like his father.
At the age of 14, Arslan goes to his first battle and loses everything as the blood-soaked mist of war gives way to scorching flames, bringing him to face the demise of his once glorious kingdom. However, it is Arslan's destiny to be a ruler, and despite the trials that face him, he must now embark on a journey to reclaim his fallen kingdom.

Mori, a child found by a rescue team in an abandoned house, wakes up in a shelter. While adapting to an unfamiliar life, one day, he begins to be looked after with unconditional love from a mysterious sponsor... And then Mori learns about the existence of a "mom" when a close friend leaves with hers. The child starts to wonder about the sponsor: "Could this person... be my mom?"
This is the story of Mori's long and challenging journey to find his mom.

Note: Won the Readers' Popularity Award at the 2023 Naver Webtoon Greatest Contest.

Yusung is a genius doctor famous in the medical world.
He, who spent his whole life in an operation room, died in a traffic accident, and when he woke up, he was in another world.

But…a saintess? A holy empire? Healing magic?

“I put so much effort into learning medicine, but now all I need to do is touch someone and they’re healed?
Seriously, I think I’ve gone crazy.”

Sana, the daughter of an item shop in a corner of the castle town, went out to the forest to pick medicinal herbs as usual in order to make recovery potions for the store's products. There, Sana picks up her mysterious book.
Because she read the strategy book, the daughter of the item shop, who shouldn't have anything to do with the story, is greatly involved in the story of the game!
Another world romantic comedy adventure fantasy!

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.

The worst talent that no one can compete with.
Unstoppable Demon God, Dan Uhyeon.
A thousand years after being sealed for the misdeed.
A thousand years was enough to get rid of Dan Uhyeon’s sense of superiority.
A world that has changed, solitude with no one knows, and the only thing left is despondency and emptiness.
“Time goes like the wind. There’s really nothing left.”
A little girl who appeared in front of Dan Uhyeon lost her purpose and will to live aimlessly. Hwa Somi.
For a girl who seems to have nowhere to lean on, Dan Uhyeon feels the same and gradually begins to open the door of his mind.
“I’m Dan Uhyeon. Come with me.”
The story of a warrior with an icy heart and acute and pure girl
The story of an unusual family’s life in the midfield will warm your heart.

An unappealing otaku awakens in the body of a pig after he passes out while eating raw pig liver. Pig finds himself in the company of Jess, an innocent girl who can read people's minds, and she accepts him despite his boorish thoughts... although she does plan to eat him. When Jess is in danger of succumbing to a dark destiny, can Pig save her using only his quick wits, wisdom, and refined sense of smell?

In the year 200X, a Japanese fleet consisting of 3 vessels leave on a mission to South America. After encountering a storm, the ship JDS Mirai find itself without its escorts and in the year 1942, traveling towards the island of Midway to face the American fleet in one of largest battles in naval history. The crew of the Mirai must decide whether or not to change the course of history by involving itself in WWII.

Won the Kodansha Manga Award for general manga in 2002.

From CoyoMoose:

The world that was once supported by four evil Gods has fallen to a crisis. Using song and dance, it is up to the kashikans to bring back the Gods which fled from their confinement.

In the world where only the aristocrats have the power to fight the monster - mana. A youth named Kufa is dispatched as a tutor to find Mareida’s talent, a nuisance girl born in a duke’s family. If she is not talented, assassinate her. - that, is the dark side of his task.

A series about a hyper-realistic fantasy game!

"Sergeant First Class Ha, you crazy bastard. You shot another full round of bulleyes?"

The sharpshoter Ha LeeHa simply wanted to be a part of the army forever. However, due to an unfortunate accident, he became paraplegic and was tossed back into society.

The revolutionary VR game [Middle Earth] presented a new life to him. Money obtained in [Middle Earth] has real world value! Yet, he ruined his chance by selecting the lowest-tier character!

"I'm not like the others. This is all I have."

Black gunpowder, iron balls, and ramrods... I'll show you all what a real 'musketeer' is!

Nina had a rough start to life, stealing to survive—and eventually being sold into slavery by her own brother. But to her surprise, her captor, Prince Azure, ordained that she would live the life of a princess... specifically, that of the recently deceased princess-priestess, Alisha. But despite her changing fortune, Nina won't give up her old life without a fight... and Azure might just be the one to finally match her wits. But how much can she trust Azure? And can she stop the feelings budding in her heart, knowing she must eventually marry another...?

Note: Won the 46th Kodansha Manga Award for Best Shoujo Manga in 2022.

One day, all the eighth grade students were transferred to another world.

The princess of the other world summoned them to make up for their lack of strength. The students are threatened and decide to follow the princess, and they are made to take a magical power test to determine their abilities. While everyone is sorted according to their results, Kokubun Kento's result is a flop.

Judged as useless, he is expelled. However, there is actually a tremendous ability lurking within Kento...

The life-size eighth grader Kento, together with his fellow skeletons, aims to rescue his classmates!

Licht, a young man who has the special ability, [Resurrection], makes his living as a member of an S -Rank Adventurer's Party.

However, the King, who feared his power, ordered his comrades to betray him, and in the end, executed him in an unfair manner.

But Licht, who was fortunate enough to be revived because of his own skill, now swears to carry out his revenge on Humanity…

A man who yearns for freedom is reincarnated and he chooses the undesirable job "Carrier"--The fastest way to conquer both women and other world with wisdom and courage! A new erotic fantasy series from Nocturne Novels!

Imagine a world where everything you write takes life...What would you do then, if paper which had disappeared for more than two hundred years came back in the of Black Fowl, the biggest criminal mind of the century? An exceptional situation calls for excptional measures. The Police forces of City Hall will have to call to the rescue two of the best of London: Jules Verne and Arthur Conan Doyle!

The human army lost the battle with the vampires on Higanjima. Unable to prevent Miyabi's plan, Japan has become a vampire country. Six months later, there was a one-armed man fighting the vampires in abandoned Japan! The man's name is Akira Miyamoto. A warrior who had already tasted hell on Higanjima.