From Yen Press:

Just a stone´s throw from London lies the manor house of the illustrious Phantomhive earldom and its master, one Ciel Phantomhive. Earl Phantomhive is a giant in the world of commerce, Queen Victoria’s faithful servant and a slip of a twelve-year-old boy.

Fortunately his loyal butler Sebastian is ever at his side, ready to carry out the young master’s wishes. And whether Sebastian is called to save a dinner party gone awry or probe the dark secrets of London’s underbelly, there apparently is nothing Sebastian cannot do. In fact, one might even say Sebastian is too good to be true or at least, too good to be human.

Lucas has a hard life. In his mid-thirties, a mixture of failures has left him old and crippled, playing pack mule to a couple of young adventures.

Then one day, he pulls a magic sword from a stone that tells him he has been chosen to become a hero. Given a youthful form, Lucas must use the power of the sword to vanquish evil and attain a massive harem.

Before you ask, it’s not isekai because he’s been in this world from day one. It is wish fulfillment, though, so in the end it’s basically the same thing.

Tokiwa, a university student, is invited to a three-on-three blind date by Suou, a fellow classmate. On the day of the mixer, he goes to the pub where they are supposed to meet, only to find a group of handsome men waiting for him...

The Hero’s party was attacked by a large group of powerful devils. The party will no doubt be annihilated if this were to go on.
One member of the party, the strongest mage, Rakku decided to stop the enemies in their tracks.

Hyakkaou Private Academy. An institution for the privileged with a very peculiar curriculum. You see, when you're the sons and daughters of the wealthiest of the wealthy, it's not athletic prowess or book smarts that keep you ahead. It's reading your opponent, the art of the deal. What better way to hone those skills than with a rigorous curriculum of gambling?
At Hyakkaou Private Academy, the winners live like kings, and the losers are put through the wringer. But when Yumeko Jabami enrolls, she's gonna teach these kids what a high roller really looks like!

Note: Placed 3rd in the DaVinchi x NicoNico Tsugi 2016 Manga Awards.

Meet the Evil King Valt, ruler of the Continent of Darkness. After being defeated by a group of heroes, he was reborn as a human, with his powers intact!

"I'll start over in this world. And this time the whole world will be mine!"

Valt garners the attention of the elite adventurer Iris. With Iris as his guardian, he enrolls at the Royal Adventurer Training School and immediately surpasses his seniors with his abnormal power! In an unprecedented move, this maverick is designated "level 0." He goes on to employ his talents as an Evil King to great effect, dominating the new world he finds himself in...

Sasaki, an overworked salaryman, goes through an average stressful day just for a single light at the end of the tunnel: Yamada, the always-cheerful clerk at his favorite convenience store.

One day, Sasaki takes an extra amount of time at a company meeting, and by the time he gets to the convenience store Yamada has already clocked out. However, as he leaves, he notices a young woman with piercings smoking behind the store?

Note: The manga won the 2022 Next Manga Award in the web manga category.

A manga about general car appreciation, or "Car Life" as it is known to auto enthusiasts.
The main character's father passes away. On the will states that each of the three siblings receives a portion of the father's wealth. The main character receives a Porsche Carrera. She doesn't know what a Porsche Carrera looks like, didn't know the car company Porsche, can't drive a manual and had absolutely no interest in cars, at the time. You can follow along and find out what some car enthusiast do.

An elemantary schooler, Usami Kyuu encounter Ichiko, a female robot trying to learn about [heart]. What awaits the two that start to live together... Boy X Robot Girl, Begin!

Typical company employee Tanaka Daichi (38 years old, single) loves games and plays a new type of VRMMO called "One More Free Life Online" under the username "Earth". Inside this free world he chose several skills that are generally regarded as useless. Be it wasting time crafting potions, cooking up pointlessly tasty food, or hunting monsters with some absurd weapon he crafted, he simply enjoys playing the game.

Web Manga

From MangaHelpers:
A young noblewoman once dreamed of becoming a magic user like in the old tales, but her time in magic school has dimmed her passion. One day, a mysterious man comes to her rescue in the forest, using magic like in the old stories. Despite the fact that he is clearly skilled in magic, he is thrilled by the idea of learning new techniques. Since the only way to do that in this day and age is in magic school, he alters his appearance to school-age and decides to accompany her back to school.

Jung Yeonshin was born with a short fate: being unable to live past the age of twenty. Although everyone in his family looked down on him, his skills were remarkable enough for him to create his own martial arts. One day, Yeonshin realized that he doesn’t have much time left to live… This is where Jung Yeonshin, a terminally-ill genius, begins his desperate struggle to survive!

The protagonist Kim Chulsoo works his ass off for a living as a manual laborer in real life and by grinding for and selling items in a game.

He finally gets the chance to switch to a hidden class, hoping for that one big shot in life…!

But the hidden class turns out to be... a Goblin Summoner?!

Shinichi Kudo is a high-school student who, by using observation and deduction, is good at solving mysteries. While investigating one, he is caught by the criminals that he was watching and forced to take an experimental drug. Leaving him for dead, the criminals disappear. Instead of killing him, however, the drug turns Shinichi into a little kid.
To preserve the illusion of his 'disappearance,' Shinichi adopts a new name based on his favorite author (Arthur Conan Doyle) and becomes Conan Edogawa. Ran, his (actually Shinichi's) childhood friend takes this little boy under her wing and brings him to her home.
Conan now lives at a detective agency run by Ran's father, but his mind is as keen as ever and he continues to solve mysteries... always allowing Ran's father to take all the credit.
As far as everyone's concerned, Conan is just a little kid anyway... even to Ran. This is *extremely* frustrating to Conan since nobody will listen to a 'little boy.' Despite this, Conan has a mission... to find the criminals who did this to him and get the antidote to that drug.

Note: Won the 46th Shogakukan Manga Award in the shōnen category in 2001.

When I confessed my love to Sasaki-san... she's floating!? But only by 1 cm off the ground...!
From the novel posting site "monogatary.com," a mysterious youthful romantic comedy about Sasaki-san, who can use a little bit of amazing magic, and me! (From Comic-action)

After losing his girlfriend to a brave hero, Toru is expelled from his S-Rank party. With a feeling of sadness and pain in his heart, he defeats a demon he meets outside the city, and his ability [to save experience] is broken! Toru becomes level 300 in the blink of an eye! With this power that far surpasses that of heroes, there is nothing that can stop him. Kaede, a slave he met on his journey, forms a group called the "Mangyu Brigade", and easily completes dungeons, acquires the legendary sacred weapons, and thanks to his skills, his friends level up easily! He rescued a countess who was attacked by bandits on the road, and befriended a legendary beast. Oru's journey continues at a leisurely pace, as he repeatedly encounters various people along the way, while his former party of heroes are deprived of opportunities to play an active role and fall into decline. This is the beginning of the life of a 300 level warrior!

Original Webnovel: https://ncode.syosetu.com/n9483ge/

Abandoning money, fame and honor, the knight Bard embarks on a journey to find his final resting place. Tasting delicious food, admiring the unfamiliar scenery all by himself, his journey to find a place to die quietly begins.

What he doesn't know however, is that this is the beginning of a new adventure for him.

“Huh?! Kyaaaaak!!! W-Why did I suddenly become an anchovy?!!!”

He majors in food and nutrition and has a first-class certificate as a daily sports instructor, the epitome of being a fitness enthusiast, Choi Young-jik! Well, that was who he used to be…

Waking up in the body of Prince Soo-yang, the second son of King Se-jong the Great, he lost all of his bulging muscles overnight.

Young-jik was taken aback when he realized he might be able to meet King Se-jong, his father. He couldn’t contain his excitement at the thought of meeting the magnificent King Se-jong, whether or not it was a dream or reality.

H-Huh? King Se-jong… the Great???

There sits in front of him, a chubby man who looks like he’s struggling to breath.

King Se-jong the Great appears to be severely obese and possibly diabetic… Government officials had chronic illnesses and frail bodies… Choi Young-jik, a seasoned fitness trainer with 15 years under his belt- holding the pride of the fitness community- begins to feel a fire ignite inside him.

“Alright, shall I try spreading the fitness craze in Joseon?!”

With his dantian shattering from a ki rampage, So WoonHwi was cast aside by his family.
After that, he was kidnapped by the Blood Cult, where he spent his life as a third-rate spy.

One day, he’s killed after being used to find the legendary Secret Records of the Sword Sage.
But instead of really dying, he wakes up 10 years in the past on the day he was kidnapped by the Blood Cult, along with the power to hear the voices of swords.

In a dilapidated castle, Astaroth awoke as a Demon King.
With his ‘wisdom from his past life,’ he would rule over his lands as a thorough ‘realist.’

“Demon King, why are you attacking the level 1 Heroes?”
“Defeat them before they become stronger. That is called strategy.”

“Demon King, why are you sending fake money to the enemy country?”
“To bring chaos to their economy, so they will self-destruct.”

“The werewolf troops have attacked. Should we use silver bullets?”
“Not bullets, shoot them with canons.”

And like that, Astaroth ‘reformed’ the old tendencies.
He became a lord who was loved by the people and his subordinates, and he would go on to be called the most powerful Demon King in history.