Phew, long title!
Basically a romance where the main girl is noticed by a boy for some time secretly.
The girl either doesn't know about him at all or barely acknowledges / talks to him.

Some examples are Boku wa Kiss de Uso wo Tsuku, Akai Michi and the Studio Ghibli movie Whisper of the Heart (Mimi wo Sumaseba)

Prefer it to be shoujo or josei, not shounen but if it's really good then... : )
No hentai, adult, shounen/shoujo ai, etc.

Perhaps Koko Ni Iru Yo! ? Though that might not really be what you're looking for.

Last Game?
Beauty Pop

Maybe Ookami-san to Shichinin no Nakamatachi?

Kataomoi no Mukougawa - the first story

Nijiiro Days (MIZUNO Minami) should work

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in need of romance?
uncommon, sad, sweet

Kimi ni Todoke
Bokura wa Itsumo
Dear My Girls
Himitsu no Ai-Chan
Iya da nante Iwasenai
Kaichou wa Maid-sama!
Kimi no Sei
Koibito Wa 16 Sai
Nobara no Hanayome
Obaka-chan, Koigatariki
Seishun Location
She is Mine
Sukitte Ii na yo
AAA
Ai Kara Hajimaru
Akuma de Koibito
Akuma wa Sasayaku
Boku wa Kiss de Uso wo Tsuku
Hana ni Arashi
Harem Lodge
Iinchou no Himegoto
In The Chocolate
Kareshi Toshishitakei
Murasame-kun na Tawagoto
Hana Yori Dango
Shugaku Ryoko - Naisho no Koi
Sugar Chuudoku
Vahlia no Hanamuko
Zenbu Kimi no Mono
Zettai Heiwa Daisakusen



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朝露の少女。

“The longer we live, the more weight we carry in our hearts.”