something sad like rental onii-chan please?

Hmm maybe boy meets maria?

Not totally like that....
https://www.mangago.me/read-manga/jiji_mago_gurashi/
https://www.mangago.me/read-manga/no_you_na/
https://www.mangago.me/read-manga/yuzuki_san_chi_no_yon_kyoudai/

Shuumatsu no laughter