Suitable For Work Version: http://www.nutaku.com/games/flower-knight-girl-online/
NOT Suitable For Work Version: http://www.nutaku.net/games/flower-knight-girl/

So check whether right before the final slash it has the "-online" part in the url. If it does, remove that to get the hentai version with bonus scenes.

Keep in mind which site you're actually playing on since progress is shared, .com for PG/.net for R18.

Also know that while playing the .net version you can re-watch the H-scene's as much as you like.