Replaces the Art Gallery paintings (also affects some other heists) and other gallery elements with Ashley/Leyley Graves and others from The Coffin of Andy and Leyley. The paintings include original game art, fanart, and AI art. Don't ask how many images I have of this psychopath on my computer now...
Some of the stealable paintings are visible in the preview screenshots but some you'll have to see for yourself :p
If you are interested in changing the Art Gallery yourself, you can check out my guide below. From the TOC, scroll down the to the "Texture Replacement Guides" section and then to "Art Gallery".