Very cute art style! There's a solid game mechanic in the short levels that exist. The cat only being able to climb certain walls is a bit confusing. I had fun and wanted to see what every dialogue choice led to, even if it meant being a bit rude sometimes!
I can't speak for Slartibartfast but you could definitely turn this into a great, full game now that you aren't on a time limit.
And, seriously, placing a bunch of blocks to make a level is a lot more involved than it sounds.