From MangaHelpers: Nogawa Izumi is a good student, and a class representative, but she has an increasingly high libido. It's gotten to the point that she'll claim to feel bad during class, so she can run to the nurse's office and masturbate. When she learns that the Earth is being invaded by aliens that look like people dressed up as animals, it turns out her high sex drive may be able to help protect the Earth. The first time Izumi is attacked by the aliens, she is rescued by Usayama, a bunny alien whose race was their previous victim. Usayama gives her an outfit (a sexy swimsuit) that will allow her to fight the aliens, but which also sends her constant arousal through the roof. The scientific organization that Usayama is affiliated with think that Izumi, with her high erotic level, may be the person they've been looking for to fight the aliens. Will Izumi be able to save the Earth? [tethysdust]

Akihime, the daughter of Ryokuhouzan's Long-Nosed Goblin, lives with her mother in the lower world and is attending junior high school. She continually refuses the offers of her childhood friend, Shun, who wants her to train with him in the mountains in order to become the Long-Nosed Goblin, because Akihime's heart is just too filled with her feelings for her classmate, "Takeru-kun". - Taken from Antebellum Scanlations

The title character, Maruko, is a nine-year-old third-grade student. She is lazy, disorganized and usually late for school, in strong contrast with her neat and tidy older sister who must share her room with her. Maruko, like many kids, tries to avoid homework and chores, takes advantage of her doting grandfather and squabbles with her sister. Nevertheless, she is a well-meaning child who tries to do good. Maruko's real name is Momoko Sakura (さくらももこ Sakura Momoko), the same as the pen-name of her creator Miki Miura 三浦 美紀 (who used her own childhood experiences as inspiration). Her nickname "Maruko" is made of marui ("round", because of her round face) and -ko (girl child); the prefix chibi and the suffix -chan also refer to a cute child. Maruko's trademark face fault in reaction to embarrassment is the sudden appearance of vertical lines on her face, sometimes with an unexplained gust of wind blowing behind her head. This is sometimes mimicked by female fans of the series who draw the fingers of one hand down across the face to show embarrassment. On the internet this is often used as emoticons, by speech marks. For example: -_-" Other characters include Maruko's classmate and best friend Tama-chan. A fan favorite is Maruko's kind but absent-minded grandfather. Naive and easily tricked, he keeps a pet turtle and loves watching TV with Maruko. When feeling distressed or nostalgic, he spontaneously retreats to a surreal inner world for a few seconds to improvise a sad yet comical haiku about his state of mind.

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I met a Mahou Shoujo; and so began my story.. "Then I will become a Mahou Shoujo!" In order to save Hoshi Karen, the Mahou Shoujo who had protected her even while being pursued by tanks. Kokone, who was entrusted with Karen's Grimoire, decides to become that which is acknowledged as a "Calamity" by the world... A Mahou Shoujo!

From Chibi Manga: A heroine who can see a spirit, sakura! from living with fear being threaten everyday turns into a ikemen paradise students council...? what happening..?

Minami-ke is a manga following three sisters, Haruka, Kana, and Chiaki in their lives at home and school. It's a funny manga that depicts how these characters interact with each other and their classmates. It's a manga about ordinary girls and their ordinary adventures told in an extraordinary manner. This description doesn't give the manga enough credit, so check it out yourselves.

The official spin off of Ao no Exorcist.

After three unfulfilling years of high school, Imamura Kinichirou was finally graduating. Because of his delinquent-esque looks, he was feared by his classmates, has made no friends, and his greatest regret was not joining the ouendan (cheer club), which was now disbanded. After an accident on the day of his graduation, he and classmate Fujieda Aki are transported three years back in time, freshman again in body but with high-school memories intact. Can Imamura fix the mistakes of his past? Can he re-do his high school years in the way that he's always wanted? Again!! The universe suddenly shouts.

From DrCoke at MangaHelpers: 2000 years ago, there was a battle between a warrior and the demon king. Through this epic battle, the demon king won. Now, there are kids between the ages of 12 through 18 that are direct descendants of the demon king. They each have unique transformation powers that allow them to turn themselves into varying monsters, such as slimes and golems. Imaichi Butsuko and Hinase Suiren are both one of these monster kids. With the impending resurrection of the warrior, these kids enjoy their daily school lives while preparing for battle!

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From Chibi Manga: In 365 days, there were bright days and disappointment while I was staring at you. Though they were neighbors, Nino and Kira had never talked to each other... But when Nino found out about Kira's secret, her life changes and everyday became more interesting!! Their link will lead them to a love close to the paradise.

From Chibi Manga: Aside from being transferred from school to school during her middle school years, Kanoko has entered Takara no Tani High School with Tsubaki. For some reason, she becomes the “Strategist” for Cultural Affairs Department in reference to the Three Kingdoms and ends up joining the Newspaper Club….?! *Sequel to Warau Kanoko- sama

Honori joined the suspicious-fun club, the "Substitute Club", which substitutes for people and does their work for them. The members of this handy-man type club are very free-willed and loyal to their desires.

Touma Sou is an MIT-graduated-student who comes back to Japan because he wants to know how it feels to be a high school student. On the other hand, Mizuhara Kana is a strong girl who loves sports. Together, they are partners in solving cases that happen around them. Recipient of 2009 Kodansha Manga Award for Shōnen Category.

From Day of the River: An unhealthy obsession with boys' hands, voices, and other things. Protagonist Mizuhara Hiyori has a difficult-to-explain fetish. In order to live a peaceful life, she hides her fetish away from the world and entered Blue Star Academy. There, she meets Narita Naohisa, a beautiful boy who discovers her fetish one day at school. How? Because he possesses all of the lovely qualities that Hiyori fetishizes! However, Narita-kun turns out to be a rather troublesome teenager...

Marufuji Enta has a crush on Kenzaki Ameri and as they visit the same class for the first time the best day of his life starts! Ironically, he gets kidnapped until a mysterious hooded girl appears in front of the gangster's car in the name of justice! --- New WSJ Series of the may 2015 batch!

Hirayama Hayaka’s parents got divorced, and now Hayaka and her mother are looking for a fresh start in a new town. To make life easier for her mother, Hayaka decides to abandon her private school days and enrolls in an industrial high school without touring it. On the first day, after witnessing a fight between her class’s leader and an upperclassmen, Hayaka learns that all the girls in the school transferred out months ago, because the boys were really out of hand and always fighting. Hayaka is the only girl in school! The next day when Hayaka comes to school, the same class leader and his friends adopt Hayaka, and she learns that not all the gansters in school are bad! The class leader turns out to be a caring boy, who mothers all the boys in the class, and then extends his care to Hayaka. As the class leader knows that Hayaka is in danger if she stays unprotected on school grounds with so many gansters around, he puts a metal plate in her book-bag just to be safe. But when a fight ensues between the school gang leader (the banchou) and the class leader, Hayaka hits the banchou on the head with her bag, knocking him out! As school law among the students states that whoever defeats the banchou becomes the new banchou, Hayaka is the new school gang leader! As the story goes on, Hayaka gains more and more subordinates in different ways. She meets other school gang leaders and rich heirs while increasing her number of subordinates, all while unknowingly charming the class leader with her purity and determination to do the right thing…

From Chibi Manga: Ayu saw the boy she loves, the handsome teacher Hiromitsu, throwing away a nice girl. But then, Hiromitsu is treating her so hard... Ayu's real lessons will start!

The club room of the defunct Tea Ceremony Club has been taken over by a 4-person group calling themselves "The Amusement Club". A full-bodied comedy, overflowing with love, it's guaranteed to give you the energy to live healthily and heartily for tomorrow. *Contains the story Hearts Melting Together in vol. 2.

Himeno is a sweet, shy little centaur girl. In her world, everyone seems to be a supernatural creature, and all her classmates have some kind of horns, wings, tails, halos, or other visible supernatural body part. Despite their supernatural elements, Himeno and her best friends, Nozomi and Kyoko, have a fun and mostly normal daily school life!

Parasites: shape-shifting aliens whose only purpose is to assimilate with and consume the human race… but do these monsters have a different side? A parasite becomes a prince to save his romance-obsessed female host from a dangerous stalker. Another hosts a cooking show, in which the real monsters are revealed. These and 13 more stories, from some of the greatest shoujo manga artists alive today, together make up a chilling, funny, and entertaining tribute to Hitoshi Iwaaki's manga horror classic!

A chance meeting blossomed to love between two girls. But it’s quite a peculiar couple: Sayuri is ordinary in every way, while her love interest, Yoriko, is a refined lady who seems to be completely lacking in common sense. Graceful attraction between two very different personalities, a sweet and slightly dazzling love story.

[Senpai Notice Me Scans] Aiba Mikage is the older brother who likes "rules" and "order", and his brother a year younger is Tomoaki, who's loose and rough. They have contrasting personalities, but 12 years after their parent's remarriage, they have been getting along well. However, the winter Mikage's university entrance has been decided, their uncontrollable feelings break the "rules", and the two of them decide on new "rules" for themselves... Underneath their secret rules, the two of them desire each other strongly but their time to part is near. The erotic and dramatic love of step-brothers!