Formats:

anime = japanese animation, manga/manhwa/manhua = japanese/korean/chinese comics

given

Released: manga - 2014, anime - 2019

Tightly clutching his Gibson guitar, Mafuyu Sato steps out of his dark apartment to begin another day of his high school life. While taking a nap in a quiet spot on the gymnasium staircase, he has a chance encounter with fellow student Ritsuka Uenoyama, who berates him for letting his guitar's strings rust and break. Noticing Uenoyama's knowledge of the instrument, Sato pleads for him to fix it and to teach him how to play. Uenoyama eventually agrees and invites him to sit in on a jam session with his two band mates: bassist Haruki Nakayama and drummer Akihiko Kaji.

Sato's voice is strikingly beautiful, filling Uenoyama with the determination to make Sato the lead singer of the band. Though reticent at first, Sato takes the offer after an emotional meeting with an old friend. With the support of his new friends, Sato must not only learn how to play guitar, but also come to terms with the mysterious circumstances that led him to be its owner.

Media: Manga, Anime TV+Movie+OVA, Live Action TV Drama, Drama CD

Manga published in English by SuBLime - https://www.sublimemanga.com/given

Anime released by Crunchyroll - https://www.crunchyroll.com/given

Yuri!!! on ICE

Released: 2017

Reeling from his crushing defeat at the Grand Prix Finale, Yuri Katsuki, once Japan's most promising figure skater, returns to his family home to assess his options for the future. At age 23, Yuri's window for success in skating is closing rapidly, and his love of pork cutlets and aptitude for gaining weight are not helping either.

However, Yuri finds himself in the spotlight when a video of him performing a routine previously executed by five-time world champion, Victor Nikiforov, suddenly goes viral. In fact, Victor himself abruptly appears at Yuri's house and offers to be his mentor. As one of his biggest fans, Yuri eagerly accepts, kicking off his journey to make it back onto the world stage. But the competition is fierce, as the rising star from Russia, Yuri Plisetsky, is relentlessly determined to defeat Yuri and win back Victor's tutelage.

Media: TV Anime, Upcoming (eventually...) anime movie sequel
Anime released by Crunchyroll - https://www.crunchyroll.com/en-gb/yuri-on-ice

Umibe no Etranger / Seaside Stranger

Released: manga - 2013,  anime - 2020

Shun Hashimoto is an openly gay aspiring novelist living in Okinawa who was abandoned by his parents after coming out to them. Mio Chibana is a reserved, orphaned high school student, often found spending his time by the sea. One day, the two meet on the beach, and Shun is instantly captivated by Mio. The days fly by as they slowly begin to grow closer until Mio suddenly announces that he has to leave for the mainland.

Three years pass before a 20-year-old Mio returns to Okinawa to confess his love to Shun. However, in those three years, Shun's life has changed. Will he be able to accept Mio's feelings and make such a commitment?

Media: Manga, Anime Movie, Drama CD

Manga published in English by Seven Seas - https://sevenseasentertainment.com/books/seaside-stranger-vol-1-umibe-no-etranger/

Anime released by Funimation - https://www.funimation.com/shows/the-stranger-by-the-shore

Sasaki and Miyano

Released: manga - 2016, anime - 2022

Yoshikazu Miyano's troubles first start one hot summer day when Shuumei Sasaki steps into his life. Sasaki saves Miyano's classmate from a group of bullies, and after that, Miyano cannot seem to shake off his eccentric upperclassman. His silent admiration for Sasaki gradually sours into annoyance each time the so-called delinquent refuses to leave him alone. Constantly being called by cute nicknames and having his boundaries ignored, Miyano wonders why Sasaki wants to get close to him.

The shy and easily flustered Miyano harbors an embarrassing secret—he is a "fudanshi," a boy who likes boys' love (BL) manga. The last thing he wants is for other students to find out, but through a slip of the tongue, he reveals the truth to Sasaki. Intrigued, the clueless Sasaki asks to borrow a book to read, which he is given very reluctantly. To Miyano's surprise, Sasaki enjoys the BL that he receives and asks for more, marking a shift in their strange dynamic.

Although Sasaki appears to possess some personal agenda, his feelings for Miyano become complicated the more time they spend together. As they now share a common interest, their relationship is poised to change and further develop.

Media: Manga, TV Anime

Manga published in English by Yen Press - https://yenpress.com/9781975320331/sasaki-and-miyano-vol-1/

Anime released by Funimation - https://www.funimation.com/shows/sasaki-and-miyano

No. 6

Released: novel - 2003, manga - 2011, anime - 2011

For Shion, an elite student in the technologically sophisticated city No. 6, life is carefully choreographed. School, study, and the occasional visit with his friend and classmate Safu. One fateful day, however, he takes a misstep, sheltering an injured boy his age from a typhoon. Known only as Rat, this boy is a VC—a fugitive living outside the computerized tapestry of city control—and helping him will throw Shion’s life into chaos and start him down a path to discovering the appalling secrets behind the superficial perfection of No. 6.

"Sadly beautiful in places, hauntingly violent in others, No. 6 [is] worth your time." —Anime News Network   

"No. 6 is science fiction the way it's meant to be—boundary pushing ... and completely spellbinding." —Inside AX

Media: Novel, Manga, TV Anime

Manga published in English by Kodansha - https://kodansha.us/series/no-6/
Anime released by Crunchyroll - https://www.crunchyroll.com/en-gb/no-6/videos

Doukyuusei / Classmates

Released: manga - 2006, anime - 2016

Hikaru Kusakabe is a normal, carefree boy in a rock band who is always focused on the present. During the summer, his entire class is forced to participate in an upcoming chorus festival. By coincidence, he discovers his classmate Rihito Sajou—known for being an honor student with excellent grades—practicing his singing alone. Sajou just cannot seem to get their class' song right, and Kusakabe, delighted at seeing a new side of his straight-laced classmate, offers to help him prepare for the event.

Although their lives and personalities are total opposites, they begin to grow closer as time progresses. But with the pressure of an unknown future, what will become of them and their growing relationship?

Media: Manga, Anime Movie

Manga published in English by Seven Seas - https://sevenseasentertainment.com/series/classmates-dou-kyu-sei/
Anime unavailable officially in English, it's out there though - not that I can link you to it