I love math. Just after the high-school entrance ceremony, I meet a beautiful girl: Milka. Milka is a mathematical genius. She shows me many math and many elegant solutions. Milka and I spend a long time discussing math in the school library.

One year later, I meet another mathematical girl: Tetra. Tetra is one year younger than me, and asks me to teach her math. While I teach her, she begins to understand math and gradually to love its elegance.

The third series is about logic puzzles, Peano arithmetic, epsilon-delta, Cantor's diagonal argument, Hilbert's program and Gödel's Incompleteness Theorems.

A story about a maid with animal ears and her mistress.

From MangaHelpers:
Yasaka Tokiwa lives in an unusual time, and according to his dreams, it's about to become even stranger. He's been having a dream of a woman called Ri'in ever since the robot, who he calls Makina, came to his home. He and Makina attend the same school, where their other classmates include a secret ninja (Kusanagi Kanata) and a sorcerer (Yata Haruka).
When Tokiwa, the robot, the ninja, and the sorcerer rush to rescue the student council president from a demon, the boys find that they've all been having the same dream! What is going to happen to their world?

Who do you think lives next door? A college student?
A secretary? A foodie? A quiet sort?
Or a killer?

A little bit made up and a lot of it not.

A world where logic does not exist and anything is possible. The only limit is your imagination. Bite-sized comics with dry humor for the broken souls.

From Kodansha:

Class troublemaker Ryu Yamada is already having a bad day when he stumbles down a staircase along with star student Urara Shiraishi. When he wakes up, he realizes they have switched bodies—and that Ryu has the power to trade places with anyone just by kissing them! After figuring out the workings behind this new and amazing ability, Ryu and Urara take full advantage of the situation to improve their lives. But with such an oddly amazing power, just how long will Ryu and Urara be able to keep their secret under wraps?

N/A

From Yaoi Is Life:

Saichi and Kotetsu are drawing manga as a team while living in extreme poverty. At loss for an idea, both of them decided to write a “real BL” based on themselves! They rise to be a star in the BL world, but…?!

"The other short stories within explore a schoolboy crush that turns into something more, an antagonistic relationship between a wealthy heir and his crush, and the love life of Usaki, the editor of Saichi and Kotetsu’s stories" (June).

Mizuki gets confessed to by a boy in front of a special Mirror. Legend has it, that if you confess to someone you like in front of that mirror your wish comes true.
There is a slight Problem in this Equation: Mizuki is just a very feminine looking boy.
Also it seems that he caught the Attention of the Norse Trickster God Loki while glancing into the Mirror. Loki decides out of boredom to mess with Mizuki and turns him into a real Girl.

From MangaHelpers:

Shou lives out in the country. He has a big crush on his childhood friend Sora, but is afraid that she thinks of him only as a little brother. One day, Sora announces that she was abducted by aliens. Later that day, Shou confesses his feelings for her and she dies shortly afterward. Shou is still in shock from her loss, when an alien girl named Lila comes down from the sky. She has a disk that contains a brain scan of Sora, and she can run Sora's personality in her own body. She also wants to have a child with him. Will Shou be able to cope with all of these sudden changes, and will he be able to keep Sora with him after all?

The spin-off of the popular fantasy manga "Fairy Tail". Consists of 3 volumes

Volume 1: Kengami no Souryuu / Twin Dragons of Sabertooth
Sting, who became the master of Sabertooth, Rogue, Yukino, and Minerva together perform jobs together, but...? What is the danger approaching their guild and the whole continent!? The episode that was not shown in the original story is now being told!!

Volume 2: Rhodonite / Road Knight
Spin-off of Fairy Tail following Gajeel and his past.

Volume 3: Raigo Issen / Flash of Great Lightning
The story centers Laxus Dreyar, the Thunder God Tribe, and the time they were affiliated with Blue Pegasus.

Meguro Mito has always been made fun of for her chubby appearance. Her sole happiness is discussing her favorite role-play game with her two best friends. One day, while she is being bullied, a handsome classmate saves her. Is this the beginning of her first love?

A story about a long-necked girl's love life:
Kanoi Natsuki and her childhood friend Itsuki visit the same school and there seems to be more between them besides friendship. As a Rokurokubi, her quirk of stretching her neck is normal for her and her surroundings, but it's not always her choice to stretch it and although she has feelings for Itsuki, she can't tell him what she feels. Ultimately, she has to go through misunderstandings and shame.
Itsuki, meanwhile, manages to make any awkward situations dissolve or maybe not?

From Shoujo Crusade:

What does it mean to be in love? Inoue Fuuko has a huge crush on the handsome Takamiya-senpai but due to her over the top delusions, she's mistaken as a stalker. Even though Fuuko really likes her senpai, she just doesn't know how to approach him without her delusions being triggered! Find out what this total amateur in love will do to get her beloved's attention!

A weird comic for a weird world.

Misaki Hayato returns to his hometown and enrolls in the same high school as his two childhood friends. A lot has changed in the years he has been gone, his former best friends are seemingly distant from each other and leading relatively normal high school lives. Hayato's sudden arrival soon changes that and sends shockwaves through the entire town's delinquent population with his willingness to do anything for his friends and his love for a good fight.

Even if people are born with super powers, they must serve as sidekicks of superheroes in order to become superheroes themselves. Lamia a.k.a Dream Girl has the power to make people fall asleep. She is the sidekick of Darkslug, who is not a great hero compared to his reputation. One day, Dream Girl and Theo work together to get rid of villains and save the world.

Once upon a time there was a loser, but that one day he got the ability. Ask what? Well ... it's hard to explain, he knows how to instruct on "the right path" girls who strayed from it.