Aya Drevis from Mad Father and Ms Library from Misao look very similar. They have other similarities too:
- Both games are made by the same man(so a connection is possible)
- Ms Library mentions her father is a scientist. Aya’s father is also a scientist.
- Aya’s clone presumably goes to live with her scientist father and Ogre. Ms Library is seen living with the same arrangements(a scientist father and Orge/Onigawara).
- Both Aya and Library have homicidal tendencies
- They both like to read
- In Misao, the man who comes in to kill the bully(when you hide in the intestines) looks like Aya’s father Alfred with purple hair. He even has a chainsaw.
- Also, the bully mentioned that she doesn’t want to be, “tested on” by him. That hints that he is a scientist who may very well be Ms Library’s scientist father. Quite a coincidence for two scientist fathers to look so similar.
- If he was Ms Library’s dad then that was probably his lab. He has the exact same test tubes in there that Alfred does in his own lab.
- Ms Library had the book “The Red-Eyed Stranger” on her shelf. Aya has the exact same book. It is even read to her in her game.
- The music playing in Library’s well… library is the same music that plays at the end of Mad Father.
All this doesn’t include Version 3 which hints much more strongly to it(but, as it was made after the fan theory, the 3rd version was probably adjusted because the creator liked the idea).