There's quite a few but to answer your question about the drawings, there's a drawing of the professor and his wife and daughter, there is a small skeleton with a bullet hole (probably his daughter) and the drawings behind the photo were probably made by his daughter so he is trying to create replacements/ clones of his daughter (baby teeth in the tray and locks of hair), but they aren't complete. There are claw marks and blood prints around the desk implying that some of the "girls" have escaped and he's had to kill them himself.



Oh and an opium pipe and "opium" on his shopping list so he's a druggy.