@.I_Amiya_ has found an archive of the manga that inspired ZUN to create Sakuya and the characters from EoSD that has all 19 (untranslated) volumes of the series! The link is on the quoted tweet!
WARNING! The manga is a seinen so it contains topics not suitable for all audiences!
Quote
AmiPink
@I_Amiya_
I have great news for you, I found an archive of Sarai!
archive.org/details/sarai_
It's has all 19 volume, sadly it not translated but I found it!