Very good. You start out perceiving this as an anthology of short stories, which range from above thriller (Test story) to tear-jerkers (Best Friend and Savior stories), but after a while you realize they all serve to flesh out a world and story that is well developed and thought out. The character designs in each story were very well done, especially the robot ones, from the menacing Ari, to the incomprehensible Raum, to the cute Duri. I also really enjoyed how much the facial expressions were pushed in the art. And despite the generic manhwa style, all of it is still very well drawn. Also, the Fortune Tellerstory was a little bit weaker than the rest.
So considering all of this, I would give this a 9/10. I feel like I should give it an 8 but I really liked it and I don't really review much so... And I've been reading so much power fantasy studio slop on webtoons for a while so the contrast of a story like this that actually has like. A soul to it. made me enjoy this one a lot more.