This is a fine Gruescript game, similar to Robin Johnson's own. Gruescript is a parser/choice hybrid, where all actions are done by clicking links, but there are items, rooms, etc, and your actions can change depending on what items you have.
In this game, you are a Lovecraftian god who has been summoned. You go to find a party going on at a mansion, but a strange one at that. People have been locked in the basement all day, but you can't check on them until you fix things elsewhere.
There are a lot of classic puzzles: NPCs that want things, avoiding unwanted attention, codes, secrets.
Even though my German is poor, I found it easy to read (except one time I didn't pay attention and missed an important clue!) and the puzzles had good momentum, not so hard I felt frustrated but not too easy. I used the hints a couple of times, and they were very helpful.
Overall, a fun game that is just the right length for a relaxing afternoon.