From Basement Leisure:

Kazuma is a shy high-schooler who happens to be gay, and in love with a popular and handsome guy,Ayase! A while later, Ayase befriends Kazuma, having found out that Kazuma is gay, and admits that he too is gay, and has the same feelings for Kazuma! Yet all Ayase does is have sex with Kazuma, causing Kazuma to feel insecure, will this relationship work out, or will Kazuma's and Ayase's heart fall apart?

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

Izumi starts high school on a low note. For some unknown reason, rumors refer to him as the notorious Izumi, a thug who loves to fight. The truth is dramatically different. Izumi is the housekeeper for his widowed father, and spends his after-school free time doing the shopping, cooking and cleaning. He doesn't have the time or energy for friends, so his bad reputation actually is useful.

But what is the problem with Segawa and Sawatari? Why are the school idols always being so friendly with him? Don't they know about his reputation? What sort of friendship do they have in mind anyway? Why does Izumi start to feel like a ham-bone caught between two hound dogs?

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).

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

Han Summer (Yeuh-Reum) and Hyun Moo-Heum are very different from one another. While Moo-Heum is a brilliant, yet stunning son of a CEO of one of the most influential and extensive companies in the world, Summer, on the other hand, is a mediocre-looking girl - a plain Jane, who is just under an inescapable debt of 70 million! And to whom? It is none other than Hyun Moo-Heum! In the midst of this dilemma, a mysterious figure enters and intervenes with their lives. Could he be of any help to Summer or is he destined to make her life more complicated than it already is?

If I could describe it in a few words, I’d say “poetic”, “lonely”, and “deliberate”. There’s a touch of the sadness that comes at the end of summer, the transition into cold and quiet. It feels heavy with undertones. Every word seems deliberate and filled with meaning.

Princess Acacia of Libya is engaged to the the prince of Hittite. They are madly in love with each other. But Lamec, the young king of Egypt, while conquering Libya (and killing Acacia's parents) falls in love with Acacia. He brought her back to Egypt with an intention of marrying her. But Lamec is already engaged to the powerful princess of Egypt. It is because of her who gave up the throne for Lamec that he was able to become king. The Egyptian princess throws Lamec into prison because he wanted to break up their engagement. After giving up on changing Lamec's mind, she kills him.
The prince of Hittite came to try to save Acacia but failed. He died while protecting her. The evil Egyptian princess then throws Acacia into a dungeon and opens the water ways for her to drown.

All 4 reincarnated 3000 years later into modern Seoul.

Kieron made a name for himself in the newspaper world through a scoop... and Beth's life, which he'd used to get the scoop, changed for the worse. What made things even harder was that she was now pregnant with his baby. Three years have passed, and Beth's changed her name and is starting a new job. Little does she know that her new boss at the Daily Globe is none other than Kieron...

Sakura Ai, had her first love on Tokuzawa Taiyou during her elementary years. When the sweet and gentle Tokuzawa-kun transferred to another school causing Ai-chan to have a funny nickname "Granny Ai" when he left, Ai-chan tried to forget about him. But fate never gave up even when she was in high school! While Ai-chan went to her garden of sunflowers by the pool in the school, she found a phone lying on the ground. When she knew that it was Tokuzawa-kun's, she left it on the ground and ran away, knowing that the kind Tokuzawa-kun she used to know during childhood is now a frank tough delinquent, would her love for him bloom again? From Intercross: Sakura Ai has always loved sunflowers, as they appear like the sun, which incidentally also was the name of her first crush, Taiyou, in the 3rd grade. From since then, Ai has never had another love and has also become quite introverted, but after meeting a guy with the same name, somethings will begin to change… Also contains: Sugarless Kiss Ami met Kasshi-senpai when he took a bite out of her choco banana muffin. Since discovering that he likes sweets, she has given him various handmade sweets. But that doesn't stop him from having other girls around. Tsunde Renjyou Yuika and Haru have been dating for a year. Yuika is selfish and likes sweet things, while Haru is amazingly kind. But will Haru end up hating Yuika because of her attitude...

From Midnight Scans:

A quiet girl falls in love with a fourth year ikagu club member, Koushirou-san, who is a kind, serious, and charming person... But then... why would he...!?

They met. They kissed. They parted without a word. The next day, he turns up at dinner with her parents... And he's her father's stepbrother! Seven years her senior, and her uncle by marriage alone, he has been trusted with the duty of living with her as an "uncle" while her parents are working overseas for two years. Even though they're not blood-related, can Mao decide to love him and go through the struggles to be in love with him?

From Condensation:
Toujou Souko attends a Catholic high school for girls and spends most of her days ditching class and trying to hook up with guys. She's in a hurry to fall in love and often gets into trouble. Ueda-sensei is Souko's homeroom teacher and all the girls idolize him on campus. He thinks Souko's a good kid and is looking out for her best interests... Yet he never meant to encourage her to try and seduce him...
What begins as a passionate affair becomes a true and undying love... Ai Girl is an angsty love story loaded with melodrama. It should be noted that this series has adult themes and high smut content.

From Pink Rose Scans

Mizutani Yoshiki is a 21 year old working as an assistant director for TV shows. His friends from back in high school are all jealous because they think that he's able to rub elbows with celebrities but in reality, he's so far down the TV industry hierarchy that he's more the resident lap dog relegated to doing everyone else's dirty work.

One day, he gets assigned to help out with filming for the latest "it" drama. The lead female actress turns out to be none other than Fujiidera Mitsuko, the girl he had a crush on back in high school who's now become one of the hottest rising stars in the acting world.

As he quickly finds out though, she's nothing like the shy, quiet girl he knew from back in high school. What happened to her for her to have changed so much?

Includes another story
・「My dear B・F」
Ever since the car accident that ended her dreams of becoming a short track athlete, Yumi's been struggling to pick up the pieces and move on. One day, a mysterious boy who calls himself "Jiro" crashes into her in the school hallway. They quickly build up a close friendship---but there's something strange about him that she just can't put her finger on. Who is he really?

1. Ai, Daro. 1
Yukihiro and Takase are salary-men working together in the same company and whom share a physical relationship. However, Takase's easy-going nature and loose relationships with women makes things complicated for Yukihiro.

2. Ai, Daro. 2
Yukihiro is moved to a new section of the company - located 3 hours away from Takase. Can their newly formed relationship stand against this sudden separation?

3-4. My Eyes & Your Eyes
Kamihara has never felt feelings of 'like' or 'love' towards another before but doesn't like it when Nakahashi points it out. Nakahashi is also of a similar state of mind, so when he suddenly confesses Kamihara finds it hard to reply.

5. Only Angel Knows
Chiaki has always had a weakness for abandoned creatures, so when he see's a man getting beaten by a gang he intervenes and ends up taking the man home to treat his injuries.

1-2. The Which Is Love?
"Sheesh, he’ll cry over any type of love. I really can’t understand it."

Nonami ended up having to comfort the heartbroken Hino after he was dumped by his girlfriend. Even though Nonami thought he couldn't comprehend it, he was charmed by Hino's honest feelings. A heartrending story of sweet youthful gravity.

3-5. Sen no Yoru

6. Love and Goldfish

7. Sen no Yoru Extra

Renji is a photography college student., just now living on his own in Tokyo. He sets about seducing a classmate, and then things start to go in direction he didn’t expect.

from Blissful Sin:

“I want to satisfy my heart and body…!”

What does it mean to become a pair of lovers? Confessing love, having sex, does that alone make you lovers? When did the feeling of falling in love become a greedy luxury?

A special publication, “Rising Feelings” and more, in this large compilation full of hard romantic love stories!
***********

This volume also features two couples that first appeared in her other work Anbalance Lover.

Arisaka x Shirafuji from ch8 here and ch1 in AL.
Eiji x Yuusuke from ch2 here and ch7 in AL.

Chapter 5's Yano x Inoue are a sequel to Chapter 1 in Body Check

From Serenus-Dreamers:

1. Ageha
Yuuri and Miu had always been best friends. They tried hard together to become fashion models. However, Miu got to debut first, and their relationship started to break down. Surging dark feelings and jealousy... what is there beyond Yuuri’s agony…?!

2. Eternal Rainbow

3. Kiss Me, Baby