From Which Scanlations:

One day, Kengo Yagami found some of his classmates teasing a turtle that lived behind their school--and he beat them up. But when the turtle spoke, he was so shocked that he kicked it as hard as he could. Unfortunately, the turtle was actually a god, and as punishment, he switched Kengo's body with his childhood friend Mitsuka's, and their new bodies are causing both of them a lot of trouble at school...

Also includes the one-shots "Kirakira Hoshi no Ana" and "Kimi wa boku no Saboten."

A collection of oneshots.

Story 1, Rabbit Costume: In a closed-off town, there is a strange disease in which people disappear along with all memory of them.

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.

Chiaki inherited the house of his late great uncle, who was a shaman and starts living there. When he finds a mysterious ring and puts it on, he accidentally summons a beautiful demon fox.

Reki is a high school girl that always acts cold and isolates herself from others. Yuta sitting next to Reki keeps trying to be friend with her in every way possible. However, her cheerful approach to Reki only makes her extremely puzzled and overwhelmed. At this time, the class president Maria gets in the middle of these two. Would she make things work for them or cause more troubles?

A short twitter series by @udon0531.

A story about a guy who doesn't think that he is in love.

This boy looks so cool, so it can't be helped if I fall in love. “We've been so close ever since middle school, so now, I can't tell him I like him...” is what Akemiya feels with an unrequited love towards Iwata. But upon entering high school and becoming friends with the two popular hotties, Fujiwara and Shirotaki, Iwata is starting to get cocky!!
Iwata and Akemiya, the super popular side characters of “Fujiwara-kun wa Daitai Tadashii” presents the long-awaited super popular spin-off series that will make your chest squeeze, give you warm fuzzies, make you laugh and make you cry ♪.

Masato, adoptive son of the Kuwabara household, has always been surrounded by prosperity... Until one day the head of the family brings home a child named Kenta. Drowning as he is in the despair of having outlived his purpose, Masato still doesn't fail to notice the undue attention the master has started paying Kenta...

Short comedy spin-off for Koi Dano Ai Dano, follow the quirky adventures of Kanoko and her high-school classmates and teachers!

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!

“Wanokuni”, a country surrounded by high walls, with an enormous tree in the center. Two brothers, Mana and Shino, live here in peace with their friends and neighbors. However, those peaceful days abruptly come to an end with the arrival of two mysterious women from the outside world… Suddenly, Wanokuni is under attack! With his friends dying around him, Mana discovers that Wanokuni is in fact a giant living creature, and that the enemy have arrived in another giant creature. Here the story begins… the brothers Mana and Shino face a great battle, which will decide the fate of their world!

A collection of slightly odd oneshots with a focus on female sexuality.

Story 3, Under the Mantle: A girl is unhappy with her boyfriend who doesn’t seem to care about her.
Story 4, Pandora: A strange encounter in an elevator.

A new interpretation of Yamamoto Shuguro’s period novel Chiisakobe, transplanting the Edo era in the original with a modern setting. A young carpenter, Shigeji, who lost his parents and his father’s building company called Daitome in a fire, swears to himself he will rebuild the company according to the words of his father, Tomezoh, “What is important for people throughout the ages is humanity and strength of will”. He hires Ritsu, who has no place to go, as an assistant at Daitome. Some children from an orphanage, who lost their home, also show up at Daitome. The beaded young carpenter’s decision to take over his family’s business is a drama filled with the milk of human kindness.

1) Happy Honey Life
Coffee shop owner Hiro has always had a soft spot for his father's former assistant Morio Takamichi, though as he's gotten older it's grown into a full blown crush. And though Morio is an openly gay playboy his only interest in coming to the coffee shop seems to be for Hiro's sweet foods.

2) Eternal Embrace
Bookworm Tomoya Kuga accepted the job in the library reluctantly, but since then he's fallen in love with Literature Professor Mikumo. When troubled sex friend Makoto assaults him in the library late one night, Tomoya doesn't realize that the professor sees them. But the next day the professor sends Tomoya away...

3) Tenohira no Kokoro
High school student Kiba Sakae has been dating his sempai Anno Haruomi for a year, they haven't even kissed! With the stoic faced Anno graduating soon, Sakae is determined to create an opportunity. A romantic weekend away will help them connect physically, right?

4) Domestic Cat Blues
Former playboy Keisuke Sanada has fallen in love with his housemate Shunji Mizunumi, though Shunji is wary of Keisuke womanizing past and doesn't trust him. While Keisuke is trying to gently woo his reluctant lover, a woman from Keisuke's past appears! Will it be too much for their fragile relationship to handle?

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.

The servants and Lady Florentina's family noticed that Lady Florentina seems to have love sickness. What is truly going on with her?

A “delinquent” who freezes up and says violent things when around women meets a small girl in the library when he's out studying. To his surprise, she tutors him, even though an elementary student shouldn't be able to. As it turns out, she's a high school student and his classmate; she's eager to befriend him. Also, surprising to him is the fact that he isn't afraid of her. Could it be because he sees her as a kid? Or does he?

From The Waffle House:

Chiya brought Michiru to a very interesting cafe on her birthday. Upon eating the customized dessert, she was possessed by a prank-loving witch who intended to bring misfortune to the other ten boys who had also ordered from that day's special menu?!
Join Watanabe in this fun, magical adventure!

sidestory to be scanlated