It is a bit slow developing, but so far I've actually rather enjoyed it. It's gone an unexpected path, and I've very much enjoyed that. I'm also happy to say that the isekai was nothing more than an excuse to set up a legitimate story. Maybe that changes later on, but so far so good.
I'm pretty interested so far. If there's any isekai I'm actually into, it's the type where they level up and evolve and the like. It was a little slow after the brick eater part but it seems things have started to pick up and take an interesting turn (hopefully).
Also, for anyone feeling like they've been baited by the busty dark on the cover...
I'm pretty certain you don't have to worry about that seeing as how the recent few chapters have introduced the zombies getting "fixed" I'd say it's pretty obvious that the female zombie has clearly taken that step closer to looking like our cover girl here. Only a matter of time I say before that becomes her actual appearance.