suggestion

Rental onii chan
Sea foam
World's end garden
Nageku shinigami
Reimei no arcana

omgggggg thx thx thxxxx ヾ(☆▽☆)(≧∀≦)

Raion Gotoki no Kuni Kara (Yaoi) manga
A Wisdom Tooth manga
Hishakaishindo (Yaoi) mangaTrace Of You manga

Don't know if this is emotional enough but it be sad
http://www.mangago.zone/read-manga/see_you_later_mermaid/

This is sad but idk if 50 chapters would count as short or long
http://www.mangago.zone/read-manga/december_rain/

High School Lala Love (Yaoi) manga
Outsider Communication (Yaoi) manga