The son, tired of his overprotective mother that has a son complex with a huge imagination for misunderstandings for him and will protect him from all.
Tries to go on an adventure but his mother tags along whether he wants it or not.
NOTE: The mother is the strongest person in the country (OP level)

In a world where humanity escaped underground to survive, En is an impoverished boy who lives off the trash of those more privileged than him. He spends his days in the slums, looking through a trash heap for the decomposing bodies of "losers," those who were defeated and killed in the "Battle of the Six Realms." To participate combatants have to undergo an expensive "body modification surgery," and En sells these modifications, machines attached to their bodies that significantly increase fighting ability. Uninterested in the tournament and its champion, unlike everyone else, he aims only for a worry-free life. But one day, a chance encounter with a mysterious man shatters his reality and puts him on a different, more gruesome path.

[From Viz]:
Being a teenage martial artist isn't easy, especially for Ranma Saotome, who went through a major transformation on a training mission with his father. After an accidental dunk into a legendary cursed spring in China, Ranma now changes into a girl every time he's splashed with cold water. That would be enough to complicate anyone's life, even without the arranged fiancée who doesn't like him (or says she doesn't) and the constant stream of rivals and suitors for both his male and female forms. What's a half-guy, half-girl to do?

Robotic armed freedom fighters fight for Earth's future in this intergalactic tale of the pursuit of freedom. After Earth's overpopulation sends humans offworld to live in space stations, they are abused by the controlling power—the Earth Federation government. Colonists form the Zeon Dukedom to resolve their disputes and wage the One Year War for independence. For over 20 years, the world of Gundam has reigned over all other mecha anime and manga series. Mobile Suit Gundam: Blue Destiny continues the Gundam legacy with the adventures of Federal Forces second lieutenant Yu Kajima and his special unit of mobile suits.

Raising a hundred heroes and ending the war with an evil god, Eisen is the prophet that saved the world. Having received a great injury from protecting the heroes, he left for the Other World to recover. In that time, the heroes made use of their abilities to contribute greatly to the development of the world. Longing to meet again with the master they admired, they reported to him of their achievements in detail. Reading their letters, Eisen makes a decision to set out and pay each of them a visit as he travels the country to sightsee.

The hilarious adventures of the eldest apprentice of a sect who has a problem with his brain.

Dong Fang Xian Yun is reincarnated as the eldest disciple of the Care-free sect. But the only thing that goes through his mind is to make sure he doesn't end up dying by the hands of the "main character". Read as he makes no sense to his sibling disciples while avoiding flags left and right.

Korea's first ever webnovel of the 'another world' genre, Memorize. The legend has returned in webtoon form!] Hall Plain, a different world from Earth. After being discharged from military service, Kim Su Hyun is suddenly abducted to the world of Hall Plain. After many twists and turns, he manages to reach the peak of the Hall Plain. However, all the anguish he had experienced during his 10 years in the Hall Plain left him in despair. To change his bitter past, Kim Su Hyun decides to use the Zero Code's power to turn back time 10 years. "It is absurd to use an object with such incredible power to simply turn back time. I will ask for the final time. Player Kim Su Hyun, do you truly wish to repeat those ten years of torment?" Seraph looked at me like she was pleading. I couldn't help but laugh for no particular reason. For no particular reason indeed.

He can’t even kill a person, but he’s a villain? What kind of Villain is that? Kim Dong Jin, a high school student who calls himself a villain and explores the dark side. And this villain’s fatal weakness is…

A promotional one-shot for "Kamen Rider Decade" published in Tele Manga Heroes.

Zeff Einstein spent his whole life mastering red magic and was finally recognized for it, yet a new spell that was soon created revealed that his talent for red magic was his lowest. Bitter at the thought of all his wasted effort, he creates a spell to send his old self back in time to his younger body and together with the determined "genius" mage Milly and the handsome swordswoman Claude, he intends to master magic more efficiently this time.

I, Takayama Aruto was summoned again in replay mode, keeping all of my past stats. This time, a large Hero’s Summoning was conducted which brought along the whole class. Sick of doing the job of a Hero, I hid my stats from the others and chose to become a merchant. But, I must have hidden my stats so well that our summoner thought I was trash and was casted aside. So, I decided to form a party with the three beauties in my class who were similarly thought to be useless (a Tsundere, a lolita and a meek girl)! But, it’s okay. I still have my Item Box and Item Shop. I’ll just have to make whatever it is I need! And so, I led a relaxed life in another world creating items DIY and hawking, but…… The Dragon Demon Lord and my past wife, a succubus comes knocking on my doorstep and seeking love. It seems that the transmigration this time is going to be troublesome yet again!

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TL;DR Version: OP Harem Isekai Protag gets Isekai'd again (with his entire class this time), hides double OP abilities for slow-life living, starts new harem with girls from the class and the harem from the first otherworld that followed him to this one.

An unimaginable talent without rivalry. Will it prove itself to be a blessing or a curse?

The Remake of Volume two of Bastard!!.

Kazuyoshi Ishii has had a bad day. The former director of K1, one of the world's greatest karate tournaments, was arrested for two years for tax evasion. Just as he is released and he can return to karate, he is struck by a truck
However, just before his death, a talking cat appears before him. The cat explains that while Ishii is dead, it can give him a new life - so long as he can complete a task for it. With no other choice, Ishii agrees. Succumbing to his injuries, Ishii falls to the ground, dead
At that moment, high school girl Kei Ichinose wakes up from a three-day coma

The story follows Kakujou Youkuo his fifteenth birthday in a seemingly normal world where medical technology has sky rocketed and is now able to translate any human organ. Those behind this are called the Ame No Tori (Rain of Birds). But it all turns out to be a plot against humanity where the new tech can take over its host and thus making them into a killing machine. A task force called the Jackalope are set on annihilating them before they raise more havoc and so Youkuo's new life begins.

The year is 2014, a new substance, SDE01, commonly referred to as "Mana" is discovered by a group of Russian scientists. The world plunges into a development race to find uses of this new seemingly unlimited source of energy that cannot be seen or felt.

16 years after the discovery, it's now the self-proclaimed Age of Magic, where you can download an App to your very phone and cast magic. However, heavy restrictions have been imposed over the available spells, and the required paperwork to even use a high level spell are astronomic.

Among the citizens of this new world, a red robed mysterious man seems capable of wielding extremely powerful magic in a way that should not be possible. It's unknown what his aim is or what he wants to accomplish. All that's known about this mysterious person is that he has been using forbidden level spells to kill evil-doers throughout the city.

But detective Kim is in charge of catching this murderer/hero. And he doesn't plan on giving up.

Can a generation of god king be reborn in this world that is not friendly to mankind, can Tang San recover his wife again? What kind of path to rebirth will the all kinds of strange monsters and gods bring to him? All in the journey of a generation of gods to chase his wife, the fifth part of Douluo Dalu, with a reborn Tang San!

A special tonic found among Rome's ancient catacombs is consumed by three stray puppies, giving them incredible powers of super strength, amazing intelligence and lightning speed. These three dogs - Ben, Uru and Puchi - swear to defend a boy who has a map of a hidden treasure in the Silk Road, all while fighting against evil organizations and even competing with one another to help their master.

Edo, 1855, in the Hill of the Three Hundred district: Japan's isolationist foreign policy has been lifted, and the era of the Bakumatsu has begun. The samurai Ibuya Manjiro, 26 years old, has just begun his career as low-ranking retainer to the minor daimyo Lord Matsudaira. Tezuka Ryoan, 29, a disciple of Dutch medicine, has just been accepted as a student at Teki Academy in Osaka. Each has a temper to go with his talent, and in a time of brewing upheaval the two are not slow to find trouble, which brings them together in spite of their mutual dislike. Tezuka is called in one night to sew up Ibuya after an illicit duel; a few weeks later, Ibuya finds himself the only thing standing between Tezuka and a gang of swordsmen sent by the head of medicine for the Shogunate.

Note: Won the Shogakukan Manga Award for general manga in 1984.