In the spring of Kyoko's first year in high school, Eiko, a girl like a sister to her, returns with her younger brother, Jiro. The return isn't that big of a deal, but Jiro (self-proclaimed super mad scientist) has it in his head that he wants to operate on Kyoko! And, what's even more, the two of them are actually high ranking members of an evil organization on the run from the heroes of justice!
As if high school didn't have enough problems already, now she has to deal with these two living with her.

By the same mangaka of Nyoron Churuya-san:

Yume Midokoro is the tale of a girl whose dreams suddenly become semi-reality, as she meets a clone of herself from her dreams

From JShoujo Scans

Imaginary Ocean
Doora is always talking about the ocean and claims she's a mermaid. But is she really?

Trance's Purchase
Trance goes to the slave market to buy a slave. His cousin Palfiena wonders if he'll buy a useful slave. She's afraid he might make a wrong decision. When Trance comes across a cute girl who can't speak, he'd like to buy her, much against Palfiena's wishes. She thinks he's being fooled, but Trance buys her anyway...

Kianna's Tail
Kianna is a mermaid of the northern ocean. She lives a peaceful life there with her friends, until a guy arrives who wishes to kill her.

Karen's zippers
Ever since Karen was little, she always wore clothes with a zipper.
When Karen becomes an adolescent, her parents tell her she shouldn't open her zipper in front of anyone anymore. But when Karen falls in love with Rob, he discovers the zipper on her belly and opens it??

Selma's Jingle
After a lot of strict music lessons, her teacher says she's finally a full fledged musician. He tells her to go share her beautiful music with other people.
Selma goes to neighbouring Mokumoku kingdom to play for the royal family and their guests. Everyone loves her music and request her to play more but Selma promised her master she'd only play once a week. The prince doesn't like no for an answer though, and says he'll marry her if she plays for him...

Walking home from school one day, Noriko is innocently caught up in a terrorist bombing. Rather than being blown to bits, she finds herself transported to another world; a world in which darkness seems on the rise, as its powers desperately search for a being known as the Awakening whom it is said will awaken the Sky Demon. She finds this new world to be dangerous and overwhelming, and Noriko has little choice but to throw her lot in with the mysteriously powerful man she encounters upon her arrival. The enigma of this world and her role in it will gradually unfold, but first things first: Noriko must learn their language!

In 2004, this manga won the 35th annual Seiun Award for best science fiction comic.

By day, Kusakabe Maron is an ordinary high-school girl with more than her share of problems. But by night, she is Kamikaze Kaito Jeanne, the reincarnation of Jeanne d'Arc, also known as Joan of Arc. Her mission: to hunt down demon-possessed paintings and exorcise the evil spirits! Too bad accomplishing this mission puts her into conflict with the authorities, who view her as a mysterious stranger vandalizing works of art. With only the help of angel-in-training Finn, she must survive high school during the day and battle evil by night!

A series of light novels ispired from the manga has also been published in 2013, written by Matsuda Shuka and illustrated by Arina Tanemura.

One day, suddenly... a night where the moon shines like never before, a boy meets the otherworldly Serin, a denizen of Chaos, only to die and become the undead. Now immortal, he can no longer exist with humans due to an ancient law... A tale of revelations that begins as he returns to Chaos, the start of a new adventure!

Hardworking level one magician Konoha is apprenticed to lazy Knight Protector Saionji Ikumaru. They both work to keep the ether world sealed away from their own but sometimes the seal doesn't work. Dragons, demons, and now Ishtar, the goddess of Venus. Will Ishtar help Konoha win her master's affections? Or will she take him for herself?

Kane Blueriver and Canal, his AI companion, are trouble contractors who take jobs which require their special skills. This could go from armed escort, to patrol, to capturing dangerous criminals. Milly is a private eye who has to be the best at everything (uchuu ichi!!). When the three of them get together, they run into one mess after another, gradually uncovering more of a mystery that ties the legendary Lost Ships to all of their pasts, bringing them closer and closer to a discovery that something called Nightmare would rather not have them find...

Saiki Takaya, a guy who is easily misunderstood, one day finds a flask containing the succubus Lilim. She is very attractive but, she also has the tendency to drain the life force out of people. She surprises the life out of him (literally) when she kisses him unconscious. Lilim then flies off for more "food," but returns later, saying that Takaya's life-energy was the "tastiest." From then, Lilim is accepted by Takaya's parents as a live-in girlfriend of sorts, and Takaya's heart seems to start wavering towards this voluptuous devil.

From: Easy Going Scans

Fantasy Action Legend that follows brother's diary!!
After his brother Loki's death, on Tyr's 17th birthday.... Loki's diary is delivered to Tyr. When following the diary step by step, Tyr realizes that everything that's happening around him is already recorded within the diary.

Rinne Ikaruga is just your average 16 year old girl, trying her best to get by. One day, she receives a package addressed from her sister, inside of which is a little girl who just happens to be part planarian and can multiply.
A planarian is a kind of non-parasitic flatworm organism.

Pilot for D. Gray-Man.(http://mangapark.com/search?q=dgray-man)

Fujita is a second year middle school student with a face as pretty as a girl's. On top of that he's whimpy and a bit of a crybaby so he's often confused for a girl. Echo-chan is a fairy who promises to grant his wish and turn him into a strong and attractive man capable of sweeping Onigasaki, his unrequited love, off her feet if he agrees to help her.

In the Noramimi universe, most families own a 'mascot'. These strange and amusing creatures live at home and act as companions for younger children.

Noramimi is one such mascot. Unfortunately for him, he is an ogre type and thus not popular with children, who prefer 'cuter' alternatives. Unwillingly, he decides to 'home stay' at "Hello Kids" - an agency that organizes matters between mascots and humans.

But, like all mascots, his heartfelt wish is to one day be adopted by a family...

Matsuri Ichimatsu, Haruno Koume, and Sanguubashi Takezou are old friends with one thing in common: despite their good looks, they're incredibly unpopular with the ladies. But what does Polaris have to do with their fate? And will they ever get that harem they've always wanted?

From Beast's Lair: Based on the Doujin Fighting game, Melty Blood, made by the Doujin group, Watanabe Seisakujyo (now known as French Bread). This story is one of two side-story sequels occurring approximately a year after the 'good-ending' story of Arcueid from the original Type-Moon game, Tsukihime. One year has passed since the 'Serial Vampire Homicide case' was solved by the deaths of Nero (Nrvnqsr) Chaos and Roa/Shiki Tohno. But now the rumors of serial murders are happening again. And so, once again, Shiki Tohno patrols the city to find this phantom killer. On patrol he meets--and fights--a mysterious woman named Sion Eltnam Atlasia; member of the church group 'Alchemist of Atlas', who seek to cure vampirism. But to do so she needs data from Arcueid, the last True Ancestor, to help her in her research. But this won't be easy: Ciel is also patrolling the city looking for the rumored killer, while Akiha has been acting strangely the past few days. Also, Arcueid hasn't been seen for awhile--could she be the killer...?

From Nagareboshi Manga:
There's a new pet that has been found! It's called a baby, and Asahina Tamae is the only one in her class that doesn't have one. She finds three babies one day that seem to be special. They can do things that other babies can't! But before Tamae can keep them--she has to prove herself to her mother. Out of all her siblings, she gets the worst test scores, and the last thing she needs is another distraction.

One night in the Windbloom Kingdom, Princess Mashiro Blan de Windbloom is assassinated in her sleep. Some days later, the main character, an anonymous boy, arrives in Wind City, capital of Windbloom. Using a gem passed down from his mother, he takes up the identity of Mashiro and joins Garderobe. The story follows his experiences in Garderobe and later his battles against those who would seek to destabilise the peace.

One rainy night, Wada, a young teenage boy, standing near the edge of a bridge over a raging river - is on a depressing brink towards committing suicide. Suddenly, a beautiful blonde foreign girl, named Lisa, mysteriously appears. Who is this cheerful girl? And why is she dressed as a cheerleader? Wada wasn't interested and tries to ignore her, but Lisa kicks him off the bridge, and says "try flying." And to his surprise, he does. This power, where did it come from?

It seems that there is a war between the gods and demons. And by fate, the result of this war is tied to Wada. Upon learning this, Wada does not look very pleased. Was this his purpose - his destiny? What will he choose? Does he even have a choice? Afterall, Lisa, the goddess cheering him on, is surprisingly his classmate.

From RC-SCANS:

Gook Eun-Song is your average high school girl... that is until her attractive younger sister stole the man she had a crush on. Depressed, Eun-Song purchased a bottle of alcohol and crawled into a supposedly cursed closet in her father's furniture store.
Yu Ha is your average typical bad boy. Going insane over one article in magazine, he even broke traffic regulations while drunk just to end up being chased by a couple of police officers.

Oddly enough, he also ended up in the same closet where Eun-Song is asleep from drinking too much. Yu Ha ends up sleeping in the cursed closet with Eun-Song by his side... just to find out the next day, their bodies have been switched!

Can anything else possibly go wrong for our poor heroine?