Super Dragon Ball Heroes: Dark Demon Realm Mission! is a spin-off manga.
It tells the story of the conflict between the Time Patrol and the Dark Empire.

Tenkawa Toichi is a normal, ordinary high school boy, except he has a secret identity - he is a member of the evil Phantom Organization, going by the alias Wolken. They are planning to conquer the Earth, but is being met with opposition from the so-called Angel of Judgement, Mighty Heart (Who, coincidentally, is a classmate of Toichi, Maishima Kokoro). Surprisingly, Mighty Heart is so weak that even Wolken's underlings can beat her easily, but they only figure out her ultimate weapon after Wolken accidentally comes into contact with her body...

Kogane Kokoro wanted to reach out to someone in need in the train but was unable to do so. Then a mysterious old man appeared and took down those goons with his swift movements. Impressed by the heroic appearance, Kokoro decided to become stronger. He became the disciple of the old man and started learning fencing.

what happens when gamers are summoned back to the real world in their game avatars

In the Sengoku Period (1579), there is a young woman who has lost everything, and dedicated herself to seeking strength and a death on the battlefield. Reiri once lived happily with her family, until the day soldiers came by after a battle. Her father, mother and brother sacrificed themselves in order for her to survive. She was only saved with the intervention of Okabe Tanpa no Kami, who had been sheltering in the village. In his service, she grew and learned to fight well, chasing her goal of a death in battle. However, her path to death may not be as short and straight as she hopes.

Its been 15 years after the last Great War. While the scars of wars appear to have vanished on the outside.In truth, the world has become a much harsher place.Follow the journey of Felix and Bay on their quest to find someone from their past.

In the Steins;Gate - Hiyoku Renri no Sweets Honey series:

V.1 - Hiyoku Renri no Sweets Honey

V.2 - Motto Hiyoku Renri no Sweets Honey

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• Hiyoku Renri no Sweets Honey Final

A group of 5 male high school students that call themselves the funny-face group cause trouble at school with their crazy antics.

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!

From MangaHelpers:
High-schooler Matsuzaka Satou has a reputation for being easy, but one day her lifestyle of sleeping with one boy after another comes to an end. It happens when she meets the child Shio, for whom she is convinced she feels true love for the first time. Satou may seem sweet and innocent, but there is nothing she won't do to protect their life together, including committing murder. But from where did she acquire the little girl, and how long can their "Happy Sugar Life" together last?

Included one-shot:
Volume 2: White Sugar Garden, Black Salt Cage (pilot)

Short story:
A short story was released in Young Gangan 23/24 of 2016 which is referred to below as 19.5. It was later released in Volume 6 as an extra.

From Webtoon Live and Shiro Nabi: "Welcome to Survival, 'I Am Unhappy,' the exciting game show to find the world's unhappiest person! The grand prize... is a wish granted by God!" When the victor of the game show wishes for the end of the world, God accepts this wish with a set condition: the world's end would proceed over the course of 100 days, and during that time, he is allowed to 'change his mind' only once. Oh Duk Hee, a quirky comic artist who specializes in unhappiness, is chosen by God to to make the unhappiest person on Earth happy again. With the pressure of mankind's destruction riding on her shoulders, will she be able to change his mind before it's too late? The competition to choose the world's unhappiest human?! The hybrid school fantasy action story by Jung Pil Won!

Ueno Ittou is a kind and tall high school student raised by a single mom. One day when he gets home he finds an empty house and no signs of his mother, she has left him... In that moment, a mysterious girl offers him a job with upfront payment. The job is to take care of the Josei manga author, Nobara Hifumi!

A guy decides to pretend to be a delinquent to get people to leave him alone. A girl who was a delinquent decides to act like an honor student because her parents asked her to. This is their story.

Project Alicization, a top-secret government project run by Rath, a company affiliated with the Japan Self Defense Force (JSDF), was started to create the first highly adaptive, «Bottom-up AI». By using a 4th generation FullDive machine, called the Soul Translator (STL), Rath succeeded in copying the Fluctlights (souls) of twelve newborn babies, creating a «Soul Archetype», a non-developed Artificial Fluctlight that could be copied to create new Artificial Fluctlights, which would then need to be nurtured to mature into an individual. For this reason, a virtual world, codenamed «Underworld», was created using the free kernel version of the Cardinal System, The Seed, and then transferred into the STL mainframe via the Mnemonic Visuals feature of the STL. Underworld is set in a past era, when science and philosophy were just being discovered, but instead of recreating a past era, limited terrain and certain customs were introduced so that the inhabitants of the world would form their own society.

An innocent sightseeing trip to Kyoto opens up a magical realm to shy high schooler Chikahito Takamoto. Visiting a legendary shrine, Chikahito finds himself in the mystical world of Hana and her comrades—and his immunity to their powers leads them to believe that he’s no ordinary awkward teenager! Protecting our world from violent elemental beasts, Hana and her team welcome the confused Chikahito—who isn’t quite sure that he wants to be caught in the middle of their war! One thing’s certain, though: since he’s smitten with aloof, childlike warrior Hana, he’s along for the ride, for better or worse!

Taira Capeta was a 4th grader boy. He had lost his mother when he had been very little. Although he pretended to be tough in front of his father, actually he felt lonely. One day, his father brought junk parts home from his workplace and made a racing kart. Soon, they went to a circuit to drive the kart. However, Capeta found that its frame was bent and it could hardly run straight. But, with his technique he managed the kart. Furthermore, he followed soon after the fast kart and he could nearly leave it behind. The driver in the kart was Minamoto Naomi, the champion of the East Japan Junior Kart. Looking at their chase, Naomi´s mother, Minamoto Nanako, advised Capeta to take part in the official race.

Note: Won the Kodansha Manga Award for shounen in 2005.

Naruse “Narucho” Tohru just wanted to be someone; he tried on basketball club only to find himself ended up as a mere benchwarmer. A chance meeting with his childhood friend Kusuda Mizuki brought him to the world of streetball, and after his unexpected win against famous streetball player Shu, Naruse renewed his resolve to be a basketball player. Along the way he met Ozaki Kosuke and Sawamura Masahiro, and then together with Mizuki, the four of them formed a streetball team named SCRATCH.

A slit-mouth woman encounters a young boy she's unable to scare.

While immersed in a virtual reality MMORPG game, Yuuki was transported to another world where he adopts the name of his character Grosse Hendler, his goal being to make the most of his unique ability [mail order] to be a great trader in another world! All this while trying to enjoy a quiet life... will that be possible for him?