Most of it are cropped out or edited things from BD doujins. Since there is a ton of them now, it will be some work to pinpoint where each drawing is from. Keep in mind that some Doujins have improved reprints and BD would sometimes add some smaller drawings to them as a bit of a bonus. There is also some "work in progress" art BD posted on his pixiv or circle.ms accounts sometimes back which you cannot find otherwise except now it all is more or less on this website. Cannot say I really like this coloring and editing as it is just rather basic messing with the original work. Feels a bit like bastarizing someones work. But every now and then some images show up where I don't know where they are from. I.e. image 24 and 25 are interesting especially 24 as just judging by the style it is more of a recent one. No idea where they are from, but it is very cool that they show up from time to time.The rest is just from the doujins though.