I've found some sort of portal much near the entrance while accessing this world out of pure randomness.
It requires a file named "spelude". Interacting with the two-sided "plant" will make blood splash and turn the screen all bloody.
Returning to the portal will lead Urotsuki to a bookcase-filled modified room. Interacting with the book of the bloody bookcase will... *lost communication*
File:Cursed.jpg
A welcoming bookcase~