Komugi Shirai wakes up every day at 4.30 am, to help in her sister's bakery. At the same time, her neighbor Kirato, a seemingly philandering musician, often returns home... when Komugi goes to a club to watch her best friend's band's concert, the girl finds herself in front of Kirato's band.

From MangaHelpers:

Takahashi Kiji is an attractive, popular, student council president, but he and his two closest friends are bored. Kiji comes up with a game, "The Prince Game." The goal is to bring the worst girl ever to his birthday party in a month. Kiji begins trying to romance the friendless, round-shouldered, weepy Asahi Mabi, who has just been through a harsh breakup. To his surprise, Mabi does not immediately swoon into his arms. Instead, she seems to be a human being, with her own thoughts and goals. She is uncomfortably good at seeing through some of his act. Seducing Mabi requires getting to know her, which is dangerous when his intention is for her to end up in tears...

From MangaHelpers

Kazura has her first high school boyfriend, a cute guy named Iwasaki who likes her very much. When he takes her to see her favorite band perform live, she meets the band's cool, attractive vocalist. The next day at school, she discovers a secret: the sexy vocalist is none other than her teacher, who seems totally uncool in his daytime appearance! What will she do about her boyfriend, her teacher's secret, and her growing attraction to him? [tethysdust]

From AOC Translations: A fast-paced heart pounding, and dangerous sonic love story!

Hina is busy managing the Apricot House in place of her father, but Anzu, the strange boy who lives in room 304 is quite the troublemaker.
One day, Hina accidentally breaks Anzu's keyboard and instead of asking Hina to pay for the damages, he asks her for favour after favour after favour! While this goes on, Hina discovers that Anzu is actually the charismatic vocalist for a super popular band!!! Is the lame weirdo that Hina knows the real Anzu? Or is the cool guy on stage? Hina's everyday life is changing rapidly.

From Paper Dolls Project:

Instead of her father, Hina is the one running the duties of the Building Manager in "Apricot House". One day, she accidentally destroys the keyboard of Apricot House room 304 strange resident. Hina is then asked by this strange guy to run errands for him as reimbursement. In truth, the strange guy residing in 304 is the charismatic vocals of the popular band ...... What will be his true face!? Chicks usually will change rapidly in the face of a cool stage -! Slowly, the world that Hina knows is changing. Experience this speed ​​of sound love story!