I rate this as 6.5/10, rounded up.
The art is OK, I guess the world seems OK, but the main problem is story-wise.
Everything the MC gets comes to him out of nowhere, entirely undeserved. He basically doesn't make a single decision; the bubbly catgirl is the de facto brains of the party, he is her boytoy, and she decided to power-level him because I guess she liked the way he smells or something? Because he didn't really have the chance to make much of an impression on her.
The only thing the MC has earned is his first summon, and there isn't even a flashback sequence explaining that until chapter 6.
Furthermore, while the catgirl has more of a claim to the title of MC, her past and motivations are even less explored than the nominal MC's, until around chapter 8.
The author seems smart enough, but it's like they have no grasp of story structure; at this point it's debatable whether the manga even counts as being a story.
I would rate it lower, but frankly, it's better to have no story than a bad story, so it skates by.
Finally, the most damning I can say about this manga is that I read about 20 chapters of this at some point, but when I started reading again today, I had almost zero memories or lasting impressions...