I know EH (also called sad panda) It also still lacks content lol, I have been really deep into this and know all of the common forums and trackers and it seems from my research that the best places for anime artbooks are some chinese forums I want to know tho if someone had been deeply searching like me, thank u tho
I found a whole bunch in a place I never thought to look: e-hentai.org Just look for the tag "artbook" and you already find a bunch. Or look for something more specific. Yes, you will have porn in between. Yes, its just the images without text embedded etc. But it's a decent source.
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