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...

Haizuka just wants to live a normal life, a peaceful life far away from all the trouble he's faced. But as soon as he starts highschool, an encounter with a girl and a strange creature destroys any hope of a peaceful life.

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?

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).

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?

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 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 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

Iriya Tetsuo was the nice, quiet kid that everybody knows. Until well-meant prodding on the part of Hanada Satoshi made him choose the 'easy' way out. He purposely failed the entrance exam to a good school, and picked fights so that he wouldn't have to be around Hanada anymore.

The last thing he expected or wanted was for strong-willed Kizu Ryouji to show any interest in him. The sparks fly between the two, while Iriya's best friend Kasuga Ryouta watches jealously...

Hana and her Husband, Ryuuki, are keeping a secret. You see, Ryuuki is living a double life. On one side he is a teacher at an all girls school; messy hair, thick glasses, and all. Then on the other hand he is a famous male model that make girls shriek at just one look at him. Can Hana and Ryuuki keep their secret while still keeping their love alive?

Volume 1
ch 1-3 After Five is Rain of Kiss, What To Do With Love and The Validity of a Kiss!
Enomoto is always reprimanded by his chief Tsuda. But when he stays late to finish work, Tsuda will sexually harass him.
ch 4 Meeting in the President's Office
Two office workers and one has a secret and a fear.
ch 5 Even If It's For One Moment
ch 6 Business Trip's Promise

Volume 2 ch 6 Christmas ni Naru Made Matte
A story about one of Santa Claus' sons and a reindeer.

Volume 5 ch 5 Muko x Muko!?
Misao and Eichi are the school's most popular idols. However, every morning they arrive at the same time and show their dislike for each other.

Volume 6 ch 5 Spring Love (Haru yo Koi)
Who can it be...? A chance meeting between Koharu and a mysterious window wiper, leads to his decision to abandon his post as the President of Ameya Product, just to be close to this man. But, will only this be enough for Koharu?

From Chibi Manga & Shoujo Crusade:

1-3) Air Koi
Nina has one sided feelings for Hayashino Senpai. Nina is unable to see Senpai until she clears the game that Senpai provided…That is…to find and take the exact pictures that were e-mailed to her. But Taro from the same class was assisting her And realized how odd this game is and…?!
A Painful dramatic love story!

4) Lost in a First Love

5) Love Materializes

From Divine Sanctuary & Midnight Scans:
The Senpai that I liked so much had a girl he loved. No matter how hard I tried, I was second place in his heart. That’s when I started to go out with my classmate, Haru, who was also having one-sided feelings. We started going out to empathize and sympathize each other’s feelings but slowly, change was starting to take place in our relationship too.

A small coincidence makes history!
The story of the earthlings and superhero Aimer's efforts to block an alien pumpkin gang invading earth is about to unfold!

From Fushichou:

Hikari is a quiet, shy boy who secretly admires his senpai, Kizaki. Or, are Hikari's feelings deeper than he has admitted to himself? It also appears that Hikari has caught the eye of one of his teachers. What will become of Hikari?

SideStory in v02 is not scanlated

Divided into four chapters entitled respectively 1970, 1974, 1976 and 1980, the story focuses on a young couple, Keiko and Kosuke.
They meet during high school and soon become friends. Koisuke aspires to become a famous movie director and Keiko helps him with his project in a competition. The outcome is brilliant but not much later Keiko sees him kissing another girl. During the next years they will meet again, but will they be able to overcome their misunderstandings?

1) Give me your love
A coach's attempts to get a reaction from his expressionless student becomes sexual harassment.

2) I want to become love
Sequel to one.

3) Lets hold hands
Attracted to his stepbrother, kid leaves home and becomes an AV camera man, only to get mixed up in a police investigation with detective stepbrother.

4) Atonement
Gymnast feels guilty over his former friend's childhood trauma. Especially since the guy seems to be following him.

5) Switch
Helping his twin brother end an affair with a student gets a teacher tied up with a bomb on his chest.

6) The moon shine secretly
Hayami craves human blood, and Abe faints at the sight of it. So why are these two work rivals spending so much time together?

Senoo Kaoru falls in love with an attractive freshman he meets at the library, Shinohara Akira.

Shinohara Souya is unable to let go of the memory of his beloved.

And Akira is a lonely boy starving for love.

No matter how strongly they wish for it, these feelings wrenching their hearts can never be requited.

A secret past binds them together; and the shocking truth will be revealed in the end.

What fate awaits these beasts hungry for love, in this tragic story by Hakutou Noriko?