Based on an otome game with the same name. Igarashi Yuna is a transfer student in St. Louis High. This manga covers each of the guy's routes in each chapter.

In the series:

V.1 - Storm Lover

V.2 - Natsukoi!!

16-year-old Nanakusa is spending his mundane life on "Stairway Island" where he found himself "discarded" along with 2000 other people, all missing the memories of the time just before they arrived there. The name of the island originates from the long stairway running through the island and extending up to the summit of the mountain where the witch who rules the island is said to live. The only way to leave the island is by finding what was lost. Yet Nanakusa doesn't wish to leave this stagnant island. He enjoys his life there.

That is until Manabe Yuu, his childhood friend appears in front of him, and turns his new life upside-down. Why did Manabe Yuu, the world's most optimistic person, get discarded, and who is the witch behind all these mysterious occurrences? Follow Nanakusa and Manabe as they uncover the true nature of Stairway Island.

Kami, who is gay, has given up on love. Despite not having anyone to share his cooking with, he always makes a ton of food. And along comes Waki, a good-looking TV announcer who hosts "Waki Travels! Waki's Happy Food Corner!" Although he's got no taste buds, he eats a ton and comments on the food he finds in people's homes. But he takes an interest in Kami's food and even goes to visit him at his workplace. While he's able to slowly open up to the big-hearted Waki, he's still unable to be true to his feelings when he's afraid of getting hurt again...

Tetsu is the son of a Yakuza boss who yearns for a 'sweet love', and meets his exact type of man, Senou. Senou, however, makes his living scamming people, and in turn, attempts to force Tetsu into making an adult video. A strong couple appears; "A no need to hold back" kind of chivalrous love! The story of Tetsu's childhood friend Tomoki and his Mathematics teacher, Sahara, is included.

Is there someone that you truly love? Tomiura and Shirosaki attend the same university and both know that each other is gay from an unexpected incident. They both have become close rapidly from a sense of affinity. Even though they are drawn together, will they choose to be in a relationship with each other?

Issei makes a startling request to his origami obsessed best friend, Kento, asking if he would "please take care of his prostate."

From Bunny's Scanlations and Must Be Endless:

Top student Mizusawa, third year in high school, was kissed by his drunk homeroom teacher, Takatsu (37 years old). After being told by a dazed Takatsu, that he'll stop the unrequited love he's been holding for him ever since his school entrance, Mizusawa has for the first time taken an interest in him. A few days later, ever since his secret was known, Takatsu has been scared of Mizusawa getting close to him and each time Mizusawa would shudder with excitement. However, one day after learning that Takatsu has gone to a marriage interview, suddenly Mizusawa realized that he wants the older man. Also features the adult love between a mail carrier doggy type and an ill-tempered novelist.

Volume 1 : Young Bad Education
Volume 2 : Young Good Boyfriend

From Exiled Rebels Scans:

The thing Hara Dai hates the most is people. To him, every single person is troublesome. He was bullied and bothered so much throughout middle school that he debuted as a delinquent in high school. However, whether he’s plain or flashy, it seems the only person who isn’t bothersome is the janitor.

3SM Scans Presents:

Falling in love with a painting while at a school's festival, Iku is able to meet the gentle high schooler who created it. She falls in love at first sight and with that feeling in her heart, decides to enroll in that high school! But, what happens when she joins the art club and discovers her gentle prince has disappeared and a sleazeball has taken his place?!

Have you ever confused love? In the end what is really like ... This is a funny, cute and lovely for anyone who are shoujo ai fan..

Towa has always been shy around guys, despite being a total tomboy. This has crushed her chances of ever having a boyfriend, but a perhaps fateful encounter on the first day of high school might lead to love? But will it be with the surprisingly kind "angelic" delinquent, or the popular yet secretly "devilish" prince?!

From Condensation: Momo Yamada wanted to be a flower when she grew up, but she's blossomed into nothing more than a rather homely teenager. When her grandmother passes away, Momo becomes a live-in maid for the two sons of a elegant fashion designer. After the eccentric eldest son, Ranmaru, gives Momo the makeover of her life, she discovers that her mother was a legendary Hanabito, a beautiful woman who has a divinely intoxicating scent that draws men to her like bees to nectar. What's more, Momo learns that she, too, gives off that same irresistable aroma. Although she and Ranmaru have fallen in love, their relationship now must withstand constant assault from handsome boys and men who desire to abduct and seduce Momo. *Also contains the following stories: • Akuma no Himegimi (The Devil and the Princess) in vol. 1 • Kamisama Shikkaku (God's Disqualification) in vol. 1 • Hanamaru Scoop! (Flower Garden Special Review) in vol. 2

She. Because her parents died when she was young, she had to work at her relative's restaurant.

He. Born to a rich family representing the Kiryuu family and leaping forward in the world of economy.

Whether it's birth or childhood environment. They're world's apart. They had nothing to do which each other's lives, or so they thought...

(Source: Kisu Kissmanga Scans)

Shinichirou decides to look for a job in order to pay his rent, and his teacher suggests that he work for someone at their house, doing housekeeping. However, the person who hired him was Sakuya, a girl who is the 37th head of the Shimazu family, and her job is to exorcise and eliminate unwanted creatures. Shinichirou accidentally releases one of the creatures that Sakuya captures and they cooperate to catch it. A story of comedic creature hunting begins!

Note: Read this if you are confused about the chapter numbering.

A story about two high school friends, Ohara and Kawai.

A story about a shared loved for astronomy, a hidden love for each other.

Otome is a girl who is half. During high school, she encounters an animal-loving and mildly mysterious Natsume-sensei. She is also struggling with her social relationships. With this encounter, will her school life change?

Ch 1-6 Ono slept with Yamada, a high-schooler, when he was drunk because of a break up with Hidenori. Ono thought of it as a one-night stand, but Yamada went to Ono’s workplace to look for him the next day. On top of that, Hidenori requested for reconcile. Who will Ono choose? Will it be the passionate love with a high-schooler or a steady relationship with his ex-lover? 7-8 Fire Fighter Academy, can he fullfill his uncle's dream of being a fire fighter despite having no stamina or will he find something else instead?

Included one-shot: Umaku Ikanaishi Tsuke no Houhou

Seinen is quite popular and yet he has nothing he could get himself into and had no experience of falling in love. This made Seinen annoyed with himself. One after school, he found Noiri in the music room, playing the piano and decided to learn the cello from him. It was just something that started from a whim but as they spend time together, Seinen fell for Noiri. But it seems, Noiri is hiding a secret…?