From MangaHelpers:

This 4-koma comedy manga follows the daily life of the intelligent, responsible 6th grade elementary school student Haruna Raika. She keeps busy as the elementary student council president and the classroom leader, and she even fills in for the teacher sometimes! [tethysdust]

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4-Koma comedy following the super genius grade school student Haruna Raika and her every day life. Where she's the class president, the room leader, the top student, and even fills in for the teacher when they've overslept!

Kazuma Satō, a hikikomori (shut-in) die-hard fan of games, anime, and manga. A traffic accident brings his disappointingly brief life to an end … or it should have, but he wakes up and sees a beautiful girl who introduces herself as a goddess. "Hey, I have some good news — would you like to go to an alternate world? You may only bring one thing you like with you."

He responds, "…So, I'll bring you." With that, he is transported to another world and his great adventure subjugating the demon king begins … but first the hard work of finding food, clothing, and shelter begins. Kazuma wants to live in peace, but the goddess raises one problem after another, and then the demon king's army has its eyes set on him.

Without possessing the unique skill blessed by the goddess, a boy named Kujou Kyouya failed to save the world. He was ridiculed as a “failed hero” at the interdimensional-level academy where returned heroes who had saved many worlds gathered. However, he became the strongest and most unique hero, having trained for 30,000 years in another world with the most evil demon king, Felice, who has destroyed 3,000 worlds! Now Kyouya’s unique skill is so powerful that he cannot even be defeated by the strongest heroes! The legend of a boy trained by the most evil demon king, begins!

Brad Lester, once renowned as the strongest mage, vanished from the public eye after the tragic death of his young daughter. While living a quiet life as a lowly day laborer, his beloved wife is murdered by the "World Peace Promotion Association," an organization seeking his power. Driven by a despairing rage after losing everything, Brad sets out for revenge—only to find Valburga, the leader of the Association, has been transformed into a little girl!? Furthermore, she has lost her memories and has nowhere to go. Haunted by the memories of his late daughter, Brad resolves to "help his arch-nemesis regain her memories." Visiting the Olford Ancient Magic Research Institute, the mouse-worshipping town of Brooke, and the blizzard-shrouded village of Lutz, their long journey across the land begins—. An adventure fantasy of the strongest mage and his "child" companion!!

Traveling from Kagoshima to Hokkaido (~2800 km/~1700 mi) in her trusty, bedazzled touring cycle, this is a story of 18 year old sparkling gyaru Michibata Michika!

A certain boy and girl in middle school became lovers, flirted with each other, disagreed on trivial things, became more frequently irritated with each other rather than excited… and ended up breaking up on graduation.

And so, the two of them, Irido Mizuto and Ayai Yume, wound up meeting each other in the most unexpected fashion.

“Isn’t it obvious that I’m the elder brother.” “Isn’t it obvious that I’m the elder sister.”

The children of the partner of their parent’s remarriage was their ex-lover!?

The former couple, mindful of their parent’s feelings, decided on a ‘sibling rule’ where the one takes conscious of the other as the opposite s*x loses, but—

When they encounter each other in the bathroom, commute to and from school together… along with the memories of the past and living under the same roof, just how do they disregard each other!?

Botan Ichige has just enrolled in St. Asmaria All-Girl's School where angels are said to live. It turns out that angels do indeed live there, and after an accident, an angel named Un offers Botan her halo as a snack. After eating it, Botan discovers it had some bizarre side-effects, causing her to regularly "give birth" to colorful mushrooms. Is this the life of an angel!?

Choose the world or choose her.

Ordinary high school student Shiraishi Godo harbored a "secret" - he possessed memories of a past life. In a world different from this one, he was a "hero" who saved humanity.

However, that was a story of his past life.

In this life, he was supposed to lead an ordinary school life—until the arrival of transfer student Mai Shiina turned everything upside down.

People say that the youthful days are always bittersweet, but maybe it's just bitter? Kyouko Hori is a flashy high school girl, who, despite her ostentatious appearance, excels in academics and has a family-loving character. Izumi Miyamura is a bland high school boy, who, despite not wanting to stand out in class, secretly wears piercings outside of school and has a large body tattoo. One day, Miyamura finds Hori's little brother injured and helps him back to Hori's house, where the relationship between Hori and Miyamura begins with Hori's discovery of Miyamura's secret.

One day, Hajime Tamachi, an apathetic man, receives an unexpected message from Renafalt, a friend he met five years ago in an online game, whose face he has never seen: "Senpai, how about hiring a home security guard?" Convinced that Renafalt is 200% a man, Tama arrives at the meeting spot and sees someone with a red suitcase, just as they had arranged. However, that person turns out to be a beautiful girl with large breasts. "Ah... A-Are you... Senpai?"

Some children are raised in the hands of Kwak No, After establishing a Disciple-Master relationship, the children dream of their own dreams by practicing martial arts and walking in that path to become masters. In order to make a living, Kwak No always had to leave his seat, and Seon-yu, the eldest of the children, has to take care of the Children, and He’ll be the Great Master.

Atobe Arihito is an intense workaholic thanks to his slave-driving boss, the beautiful Igarashi Kyouka. En route to an office vacation though, their bus gets into an accident, killing Arihito instantly.

His soul is transported to the fantasy world of “Labyrinth Country,” where he’s reincarnated as a “dungeon seeker”! Trying to join a guild and pick a job, he’s surprised to run into Kyouka, who also died and has chosen the job of “Valkyrie”! However, he rejects joining her party and decides to become the rare support role of “Rearguard”! But will he be able to find a party in time?

Liz who remembers being dumped by her lover in her previous life decides to live freely in her current one.

Holding a mysterious power, she was invited to the palace as a saint candidate where she meets with the crown prince who was actually her former lover from her previous life.

Though Liz looks to be the weakest among the saint candidates she is (likely) the strongest among them.

An ordinary office worker, Akira Ichijo, was attacked by a Minotaur on his way home from work.

In the next moment, he woke up in his office desk, Akira was resurrected from death, inherited his level and status, and possessed a unique skill called "Return from the Underworld" that allowed him to restart his life at a certain time.

Now Akira makes full use of his skill and everything he had to search and survive with his childhood friend Nao Nanase to face this cruel world!!

Immortal Tatsu is an ex-yakuza who’s given up violence for making an honest man of himself - but is it still possible for a devoted stay-at-home husband to get into a few scrapes?

Note: Won the Eisner Awards in 2020.

Nagisa Ootsuki shed her former self out of shame from failing her highschool entrance exams. On her first day in her new highschool, who does she meet but the girl who made her fail the exam! How does Nagisa deal with these complicated emotions?

Author's twitter: https://twitter.com/sakuragi_ren

One day, the Marquess’s daughter Julianne suddenly regained the memories of her previous life and reflected on her behavior up to this point.

A life of luxury, bullying her siblings and stalking her fiancé...... A horrible personality and overweight appearance, devoted only to wrongdoings that belonged to the villainess of the novel she read in her past life.

In any case if it is a "serves you right" fate from now on, then it will be after I get a beautiful body and soul!

She, who thought this, started a diet together with showing a wholehearted devotion to her family —?!

(GS Team)

"The Demon King Ariman" He reigns above all in hell. Together with powerfull demons. He seeks to conquer the entire world.
However, the Demon King halted his world conquest for a centain troubling matter... His daughter - Dou is too kind..?

Akira is just having an usual day at his second year of high school when he and his fellow classmates get sucked into another world through a portal! This fantasy land is called Morigan, and is a world filled with Demons, Humans, Elves and other mystical creatures. As they get debriefed by the King of one of the continents on this strange new land, they were informed that each one of them will have a class, which skills can be conveniently opened and analyzed through a "status bar", and their objective is to train, become stronger, and repel the imminent demon invasion.

Only one of them, however, will be able to become the true.

Akira found out that he got the class and with heavily overpowered stats, surpassing even those of the class. Making use of his shinobi-like skills, including subterfuge, negotiation and stealth, Akira goes into thrilling quests and unveils secrets about this strange new world, including a meeting with a cute Elf girl and others members of a soon-to-be adventuring party where not everything is as it seems...

Takashi never graduated from elementary school because of not eating green peppers. He is already 20 years and his fellow classmate Megumi is a new teacher at his school. See how this story unfolds in a comedic way.