From Chibi Manga:

5 years ago, Shin was Yumika's private tutor. Now this Shin-kun comes to Yumika's high school as a teacher trainee! But their love from 5 years ago will most probably start to bloom again?!

From Midnight Scans:

Yumika’s first love was her tutor Shin. As she hope to meet Shin once again, which really happens, how will Yumika proceed on to confess to Shin about her feelings…

From Beautiful Soup:

"1999" is an angsty and widely varied series about a bunch of teenagers. One of them is the son of a drug lord and so as you can imagine, all sorts of shit goes down, surrounded by a backdrop of convoluted and fluctuating interpersonal relationships.

This is a plot heavy manga with some mildly-explicit sexual activity.

MAL:
This plot takes a new twist to Romeo and Juliet's forbidden love. It's July 7th, 1999 in Shanghai and there are two gangs fighting for control. Only in the ceasefire zone do people live in peace. In a chance meeting Xiaoxue, who is part of the Toulon's gang, and Dawu, from the Xianglongji's gang meet by chance and without knowing they are enemies. In the heat of the moment Dawu takes him to a place he has the keys to in hopes Xiaoxue will join him, but is turned down. With a simple kiss he leaves Dawu not knowing they will meet again, but in very different circumstances

The student council president is gaga over the vice president, but her feelings may or may not be returned. In the meantime, it's up to the serious and by-the-book vice president to keep the flaky (but surprisingly effective) president on track.

A sixteen page seasonal short! Futaba, the loneliest gay student in the world, has a crush on his best friend, Toki. But Toki is straight, and Futaba will never do anything to mess up their friendship...

After she died from an accident, Ria become angel No. 5623. She could not forget her life from when she lived. She misses Ban Ji Hwan, her boyfriend on Earth, day and night.
1 year later, Ria happened to see Ji Hwan's name on the death list, the list of every names who is about to die in 100 days. Ria begged high-ranked angels to let her save Ji Hwan. Ria entered the body of So Hae, a shy girl who is tired of her life, the opposite of Ria's personality. Enduring the bullies from step-siblings of So Hae, Ria did her best to bear everything in order to look for Ji Hwan. But when she found him, Ji Hwan cannot recognize Ria...

An art college students moves in Venice to study, she starts to live in her new room, part of an old huge historical mansion and she discovers a new world of secrets linked to her young, mysterious landlord. A gothic romance story and a vampire tale which flows around Venetian laguna and roman museums; a manga rich of suggestions and images with a passional storytelling, a deep noir drawing style and melancholic mood. From Italians to Japanese. This was created for Kodansha, published on Amie. You read it Japanese style.

Kazao is happy with his life on Mirai ("Future") Island. Sure, his parents abandoned him after he was born, leaving him to be raised at the orphanage-like facility, but his life is comfortable and has his friends, especially the lovely Eiko, the girl he loves. One night, however, he has a horrible nightmare where he sees himself die in a motorcycle accident. After that, everything changes. The next day, his parents are miraculously "found" and he is torn from his idyllic life and Eiko's side to be thrust into a world he knows only from television shows and school assignments. Dropped unceremoniously in the middle of a city with only a sketchy map for guidance, Kazao is saved from wandering aimlessly in search of his new home by the cute and forward Yuu, who turns out to be in his class at his new school as well. Despite his best efforts to accept his parents' sudden return and Yuu's friendly overtures, Kazao can't shake the feeling that things aren't quite right. Nor can he forget Eiko. Why did his parents wait sixteen years to call him back? And why is the piano the only used piece of furniture in his parents' new house? The mysteries begin to pile one atop the other as the lies fall apart in this intriguing story of future possibilities and innocent romance.

From Dark Horse: A vacation fling was completely out of character for old-fashioned Carol, but her attraction to intriguing, older Marius tempted her to break her own rules. The next thing she knew, though, he'd turned up working at her hospital! Does she have what it takes to attract-much less keep the attentions of-this intimidating, sophisticated, and utterly compelling man?

Kei is interested in a woman at the gym. Imagine her surprise when she sees her in a lesbian bar!

Satou Atsushi isn't neglected by his family so much as ignored completely. Left to fend for himself, Atsushi fails to learn human speech and instead learns "cat language" and "Dog language" from the family pets. When he's eventually socialized with other children, his speech is stunted and his social graces leave something to be desired. But on his first day of nursery school, he meets a gloomy blonde with the same last name who seems to be a safe enough choice in a first friend. After developing a rather sizeable fixation with Satou Manato, he finds out that there his first friend is seriously ill and has a twin; Shuuto.

Years later, two other friends begin school and find that there are two Satous in their class too. Two Satous who, at first glance, could easily be mistaken for twins, but there's a bit more to things than it first appears...

From Aerandria Scans:

The small country of Adarshan recently conquered a territory of the Castoria Empire. To create an alliance between the two countries and secure new border alignments, the victorious Adarshan general, Alexid Deke Adars (the king's younger stepbrother), was forced into a political marriage with Castoria's sixth imperial princess Justinia. But she's only 10 years old!

Reika Ryuzaki, daughter of the late diamond collector Yoshio Ryuzaki, is a jewel specialist who fights with knuckles branded as "Krishna" in cases involving bad guys who rob or misuse jewels for their own gains. She has an advantage in fighting as she can summon spirits from certain jewels to aid Reika in making her a better combatant in the field.

"I am, in fact, one of the dead."

So says Acony, a rather mischievous girl, upon her first meeting with protagonist Motomi. Newly moved into an ancient apartment, how will Motomi handle Acony and all the bizarre residents?

From Ivyscan:

The Lord of Sanwa's son Lamkha saves Kanan, who collapsed on the road, and brings her home. In Sanwa, where the Messengers of Heaven or Flying Serpents roam the skies, a legend has been passed down the generations. According to the legend, a Holy Dragon fell from the heavens following a battle against a Black Dragon and was buried in Sanwa. What is the truth behind the legend?

A Violinist That has talent and seemingly more connections than he lets on is used to babysit a powerful SS rank illusionist girl she seems to have known him since she was young but he most likely don't remember her. ~ Yeavon

From Forever More:
First-year high school student Yuka happens to see his amazingly handsome neighbor kissing another man. However, he learns that the handsome neighbor is his math teacher. Having fallen in love at first sight, Yuka struggles to attract Gotou's attention, but Gotou restrains him with an, "I have no interest in kids."

Also contains a oneshot called Kabuki machi no Otoko (The Man from Kabuki City).

A world of supernatural where strong preys on weak. An Earth not just for humans.....and a strange ability!

1-3,7) Savage Dog
Tanimoto has been pestered by Takatoshi since the 8th grade. 5 years younger, Takatoshi has always been following him around, making him eat gross things and giving him totally useless (sometimes unidentifiable) presents. Now 27, Tanimoto thinks he's gotten rid of Takatoshi for good, until he shows up one day at his suit shop asking for measurements...

4-6) Wondering Wolf

Abara is set in a dystopian world, filled with large structures. The story revolves around creatures known as Gaunas, those who can shape bone like armor and weaponry around themselves by transforming. The transformation begins around the spine and then shapes layered armor.

The story focuses on one such Gauna known as Kudou Denji, though he uses Itou Denji as a fake name early on.

Abara means "ribs" in Japanese.

Volume 2 contains Digimortal
A mercenary in cyber-armor battles a repressive cyborg regime.

Description from Viz: The story A, A' raises a troubling question: How would you feel if your lover died - and was replaced by a clone? Could you recreate your relationship with someone who was physically exactly the same but didn't share any memories of your life together? In 4/4, teenaged Mori flunks out of an ESP training program. But when he meets Trill, a beautiful Unicorn, his latent abilities begin to blossom... In X+Y, Hagio uses science fiction to explore questions of gender and sexual identity. Time has passed, and once again, Mori finds himself inexorably attracted to a member of the unicorn race - but this unicorn is male... and so is Mori. X+Y won Seiun Award in manga category in 1985