All unique characters (including mechants, etc.) have their own portrays and full-body images. Some of them can be recruited (generally not the merchants). Some of those have unique events you can trigger with event images. I estimate there's a good dozen of such events in the game?
Then there's random characters who you can manually assign portrays and full-body images which show at appropriate times. The first post has links to image packs and I believe instructions to "install" them can be found on the itch.io page?
Other than that, the interface and background are fleshed out with graphics, a map showing your travel path, etc.
Events and accompanying images aside, sex actions are pure text in its own mini-engine which...is fun, but it has tons of unused potential. Which will forever remain such, it seems.