Love3 artwork is ok
Eroge! artwork is not allowed
Starless artwork is ok
Demon Master Chris artwork is not allowed (front image removed)
No "visible" nudity is allowed in DB images... which is an old ruling by site owners. I do not believe that is up for debate (and does not qualify for a style guide poll vote). Censored images should not be present either. So we just do not use the picture.
When figuring out whether the art is allowed or not. Basically, are the "naughty bits" visible?
ExamplesNudity but no "naughty bits" visible
https://vgcollect.com/item/161966Nudity but resolution so low you can't tell
https://vgcollect.com/item/69203I'm not certain that the Virtua Cameraman 2 back art has nudity in it, but it gives the example where a topless photo of a girl exists on a cover. When it is normal size you can tell, but when it is 20 pixels wide, its all a blur. Nudity of this type is allowed, because the image is not edited and you wouldn't be able to tell what it is without seeing a full resolution image (which we do not provide) or have the item itself in hand.
PS: I'm sure that a really low quality photo of the actual item could be used. Many items have those kinds of pictures now... that would be one way around it I suppose.