Kate's theories about what's happening in her house are probably wrong. I think it's simple: the paintings were angered about the fact she was going to erase them, so they lashed out at her by haunting her, bending reality around her, and ultimately murdering her horribly. This was confirmed for me at the end of the episode by the appearance of the painting she previously erased.
As for why the paintings were haunted? Who knows. Maybe the painter who did them put some sort of spell on them, or maybe it was specifically only the creepy, black-hair painting that was haunted. This show isn't afraid to leave things unexplained which I think is cool. It adds to the mystery.
As for why the paintings were haunted? Who knows. Maybe the painter who did them put some sort of spell on them, or maybe it was specifically only the creepy, black-hair painting that was haunted. This show isn't afraid to leave things unexplained which I think is cool. It adds to the mystery.