"00_100p" - my save file, where I have unlocked everything in the game (100% map&inventory) BEFORE the extra stage update
"00_100p_exupd" - my save file, where I have unlocked everything in the game after the extra stage update (100%map&inventory + Boss Rush in the Nitori's shop)
"00_ch" - my save file, but with max values of everything (cheat engine was used)
"01meiling" - a save just before the room with Meiling.
"02marisa" - a save just before the room with Marisa.
"03patchouli" - a save just before the room with Patchouli.
"04remi" - a save just before the room with Remilia.
"05nitori-fura" - a save just before the final room.
"05_5cirno" - a save just before the Cirno room (where you get the Ice Mantle after the fight)
"06reimu" - an extra stage save just before the room with Reimu.

Download[drive.google.com]

All saves are named "game#.sav", so you will have to rename them to
"game0.sav" - slot 1 (top)
"game1.sav" - slot 2 (middle)
"game2.sav" - slot 3 (bottom)
to assign them a corresponding slot in the game.

Your save files are located here (feel free to use Win+R):

Added 00_100p_exupd — my save file after beating extra. (Boss rush best record is not set yet)
Added 06reimu — a save file just before the room with Reimu and her shrine.

(thank you @Crokchop!) Added 05_5cirno — a save file before the room with Cirno, but I feel like I forgot something…