To answer your question, it was copy protected. So copies of the game have been scarce from the day it came out.Why is Hanakanmuri Circle this hard to find now anyways?
Does the game have some powerful copy protection or was there some malware in the previous uploads? Or is the developer that good at hunting down uploads? From what I've seen it was pretty popular amongst ryona fans.
Out of nostalgia, I wanted to play through it again, but nowadays it's literally impossible to find anywhere. All links are dead, everyone is searching for it and no one has it. :/