|“||...I hope Ib and Mary are okay... Well, as long as there are two of them, I guess...||”|
If Mary reads this book by herself, she will wonder who tore the pages off.
"Being alone is fearful. A group of two can have relief. A group of three..."
The rest is torn off...
This book references the various endings of the game. In either of the endings, the three main characters, Ib, Garry, and Mary can never all have a happy ending, because at least one of them will die. At most, two of these characters can escape the cursed gallery and live happily, such as Ib and Garry, Ib and Mary, or Garry and Mary (in Green Edition). This mostly revolves around the fact that since Mary is a painting and cannot leave, she must sacrifice somebody real, which in this case is Garry.
"Being alone is fearful" connects to the Ib All Alone endings. When Ib is by herself at the end of the game (including when Garry jumps into the mural first), her next and final decision could end up trapping her in the cursed gallery, all alone forever. This is especially so if Ib chooses to sleep on the Final Stage when Garry isn't around to stop her. This factor also applies to Mary in A Painting's Demise, during which she escapes into the real world. However, because she did not kill Ib or Garry, she cannot officially escape from the cursed gallery; therefore, she will end up all alone in a gradually dimming gallery, invoking fear in Mary until she reaches her ultimate end.
The only ending where all three characters are still together in the end is Welcome to the World of Guertena. When Garry falls into irrepairable madness, Ib refuses to leave his side, and Mary refuses to leave Ib. Mary chooses to remain in the cursed gallery forever and welcomes her two new friends to the world.