From Viz:
When goofy inventor Senbei Norimaki creates a precocious robot named Arale, his masterpiece turns out to be more than he bargained for!

This series helped launch Toriyama's career and was awarded the Shogakukan Manga Award for shounen and shoujo manga in 1982.

From Alyschu:
In the primitive world, all the youths were hot-blooded. The Faith of Totem is the direction for one to chase their dreams! Wits and Courage are our instincts for survival. The life in the Warrior Tower was tough but joyous. Shortly in the future, even if everything had already turned to smoke and mist, our friendship will never disappear.

Mihama Academy - on the surface, a closed learning environment established to nurture students who find themselves at odds with the world around them; in actuality, an orchard-cum-prison built to preserve fruit that has fallen too far from its tree.

Whatever the circumstances behind its establishment, Mihama Academy is at present home to five female students, all with their own reasons for "enrollment." For better or worse, each girl has established a routine obliging of her current situation; life moves at an idle, yet accommodating pace within the walls of Mihama.

Yet with the arrival of the institute's first male student, the nearly preposterously opaque Kazami Yuuji, the students at Mihama begin to fall out of step with their predetermined rhythms. Will Yuuji prove to be the element the girls around him needed to take hold of their lives once more, or will the weight of their pasts prove too steep a wall to overcome?

Year 20xx. In a high-tech future, where people are divided into categories according to their birthstone, there are two important things: Box, the immense virtual reality that manages the data of the world population, and Logiste, a fierce dance competition, sometimes even dangerous, whose champions are considered real stars. To Kokoro Koyomi, however, all this is precluded because of her strict father, who forbids her to even talk about it. One day, she secretly gains access to Box, but remains stuck in the virtual reality because of a bug.

A young girl answers the door late at night and looks up to see a very, very tall man standing before her.

From: Easy Going Scans

Mercenary Maruhan, the man who roams the darkness in the time of humanity's doom.

In the ancient era of the super-continent, where no border exists between the East and the West -- the race of Demonic Beasts begins an invasion against the human race, breaking the mutual non-aggression pact!

And as humanity takes to the road to seek refuge, some gather to form the ultimate army for an attempt to kill King Rhode, the Chief of the Demonic Beasts.

The intense story of one certain mercenary starts there.

Come meet these happy friends in the jungle! These are the animals from the mysterious “Jingle Jungle” village. Get ready to smile as you read the story of the everyday life of these somewhat clumsy but lovable creatures.

Chapters 1-2: Cocytus- A girl who cares very much about fitting in, and the girl she falls in love with, who wants to be honest about everything -- including their relationship. How will this work out...?

Chapters 3-5: Moratorium
Itsuki and Mao are aware of each other's feelings. However, both of them are waiting for the other to confess.

Your not so standard boy-meets-girl story. A young engineer builds a new wing for a wounded angel.

This is a story of the simple life of the three bears: the panda bear, the black bear, and the polar bear. Original Webtoon / English Version by Naver

Asakura Kosame is rejected by the girl he likes. He bought a guitar and created a song solely for the confession on his graduation day in Junior High. Unfortunately, the girl likes another cool boy from another school, whom happens to be a member of a band.
Later, Kosame enters Meirou High. He decides to join a music club and become great to show it to the girl whom rejected him for revenge. But, it turns out there is NO music club at Meiro. The one who sees him at that time is...

In the Pretty Babies series:

Part 1 - Pretty Babies (1 Volume - Complete)
Rookie detective Chikara has been assigned to the close minded, hard-faced senior detective Ibuki, One day, Chikara, who had tailed Ibuki in order to uncover his secrets, witnesses Ibuki carrying a suspicious heavy bundle out from a church. Then, after almost being run down by a car, Chikara is asked to spend the night with the beauty who'd been driving in lieu of compensation...?!

Part 2 - Heavy x Beauty (3 Volumes - Ongoing)
In the middle of the night, Ibuki suddenly calls on his superior Kiriya. Both work at the Metropolitan Police Department and have been dating each other for the last three years. One day, Kiriya's uncle proposes to headhunt Ibuki, and talks of Kiriya's own arranged marriage introduction.

"Hmm, I guess it's high time." Kiriya sighs upon receiving a phone call from former bad company...

Dong Nu was an ordinary beautiful girl in her junior year of high school. After an accident, she met a very powerful yellow-haired man. Although his behavior was a little eccentric, he attracted her attention. As she learned more about him, she began to discover that this man had a shocking identity, as he was not just an ordinary mortal... In fact, you might even call him a... Original Webcomic: http://ac.qq.com/Comic/comicInfo/id/524373

After her mother's death, high schooler Mi-Hyang packs up her belongings and enters the household of her mother's formal manager. Even though she was a daughter of a rich man, with her father and other family members still alive and well, she apparently has good reasons for doing this... So the life of smiling 24/7 Mi-Hyang and the two good-looking sons of her mother's formal manager -- with their own set of unique personalities -- begins!!

The women in the Chidori family have the reigns firmly in hand. Then a cool young man appears among them as the mother's new assistant.

Asaichi can't play any instruments and his voice is average, and he's only in a band for the girls and the sex. Plus, he's homophobic. For some reason the new bassist Yoru is infatuated with him despite the treatment Asaichi gives him.

Included "Aru Otoko no Uta": the story of yakuza Onii chan and how he had come to know Yoru.

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See also Yatamomo extra "Hashiyasume" - a crossover story

From Yaoi Is Life:

Hiroi always shared what he liked, things and people alike, with his childhood friend Take. Take always returned Hiroi's affections. Mine, who because of his deep love for Hiroi, accepts both of them. The relationship of these three classmates was in a good balance, but because of a subtle change in their feelings, this balance slowly gets unhinged...?!

From Canis Major Scanlations:

On a class trip to a museum, Kasama takes notice of his classmate Takagi, who he knows doesn’t talk to other people much. But as the latter enters a curiously shining door and realizes Takagi can see "it" as well, even his interest in the classmate is woken.

From MangaHelpers:
Maiharu Hiromi has moved from Nagasaki to Kamakura at the start of her high school years. Kamakura is a beautiful, mountainous place, with a view of the sea and Mt. Fuji, and Hiromi is thrilled to explore the area. Hiromi hasn't ridden a bike since she was very young, but she attempts to ride to her first day of school anyway. In her case, riding a bike does not come naturally, and she ends up bumping into her first friend, Tomoe, who helps her learn how to ride. It turns out Tomoe is going to be in Hiromi's class, and their teacher is also a cyclist. Now Hiromi's exciting high school life, full of new friends and learning about cycling is about to start.

From Blissful Sin:

1-2) In High School they had an indecent relationship. Now eight years later, at the school where Takebayashi is a teacher, that same Ono has come to be the school nurse. Smelling like an old man, sweet pick-up lines, totally aloof and bantering Ono. Takebayashi sighs. He gets angry, fights, and is surprised later... to find himself in Ono’s arms?

3) Ryouhei accidentally meets on the street with Naoyuki, his former neighbor friend who been nearly abandoned by its mother. It been some years since they seen each other, but how they will feel now?

4) Continuation Ryouhei x Naoyuki story

5) As it is: Tsuji is crying again because a broken heart when suddenly Aizawa, his best friend, kisses him. (Prequel to doujin Sono Mama de)

6) Has a short story Peach Sweet Home.