I might be the only person on Etsy selling erotic art coloring books, but I’m certainly not the only person sharing erotic and pin-up art:
How great is that 1960 cover for the Well of Loneliness?
You can find more mature bits and pieces on Etsy by searching for terms like mature (all adult-oriented listings on Etsy are required to be tagged mature, so you’ll find Everything that folks think is mature, plus quite a bit more that isn’t), dildo (with luck, this one will come up on the first page), erotic art or BDSM”, or you can browse the members of the Mature Shops of Etsy group. Or, if you’d like some sarcasm and snark with your adult content, you can wander over to Regretsy.
Oh, also: It’s the new Scarlet Tentacle erotic art coloring book for adults: (More) Dangerous Curves! Woo!