Well, ahm, so it's nothing like "Being a DIK", outside of the explicit 3D animated sex scenes you get as a sort of "reward" for progressing the game. There are no player choices at all, and with the help of your "Soul Crystal" you can get constant updates on what to do next. It's a generally linear experience, but it manages to stay mostly engaging throughout (I guess the cutscenes help and you can rewatch them at any time ;-) ). The characters are well developed and generally well written for this type of game.
The story is about treasure hunting, and it's actually pretty solid with plenty of twists and turns. You can definitely play it just for the story, although there are a LOT of pesky scenes that will get in the way of that experience, so consider yourself duly warned.
Extremely good value for money - there is certainly plenty of "content" that's for sure over the ~40 hours(!) it takes to finish. Currently at an "Overwhelmingly Positive" on Steam with over 2.7K reviews. There are clearly a lot of thirsty gamers out there!