Kimetsu no Yaiba suffers from fast pacing on the story while leaving the world building in awfully slow pace. The training period over very quickly without much sense of progression.

Story: 5/10
It goes with promising start, a witty protagonist that struggle to face the opponent he just can't never beat. He then saved by a strong person from 'organization' which makes him realize that he need the power that regulated by that organization to be able to fight eye level with his opponent. Classic approach, but works to pick my interest.
But from this point the story head south. The training period feels really rushed with obvious milestone that not really convince me about his progression. On the second volume he already a demon hunter that can hunt by himself, as if the only thing that needed to be the demon hunter is splitting a rock. Screams mediocrity and along with the art, it just not picking my interest anymore after the third volume.

Art: 3/10
The art is rather rough, which do not help the rushed pacing. The lack of tone makes it seemed to be losing tons of detail and the fighting scene fells dull, static and outdated.

Character: 4/10
The main character is your typical good guy protagonist: naive and want to help anyone he met. Rather boring and mediocre.
His sister's position in the story is kinda awkward. She's the last surviving member of his family that infected and need to be cured; the goal which the protagonist try to chase. But she also act like a convenient tool in the story. Despite being infected she's able to control the power and even entering hibernation mode when necessary just too make her not consuming another human being. It's just like her personality is a blank slate. Being unable to communicate verbally worsen it.
Another side character... they just forgettable

Enjoyment: 3/10
The most horrible thing about this manga is the humor. I know the author trying to insert jokes here and there since they're pretty obvious, but they're just not anywhere near funny. For example, there's one character that keeps repeating joke over and over again: he's nice to the girl he like but absolutely rude to other people. repeat. Nice to the girl, rude to others. Repeat. HEY! I GET IT! HE LIKES THE GIRL! HE LIKES NO ONE ELSE BUT THE GIRL! I GET IT! JUST STOP! Another character: Proposing marriage to every girl he see. Repeat. HEY! I GET IT. HE REALLY DESPERATE TO GET A GIRL TO THE POINT HE PROPOSE MARRIAGE AT THE FIRST MET. NO NEED TO KEEP REPEATING THAT! JUST STOP IT!
Those repetitive jokes are filling one and a half volume, and this is the point where I sick of this and drop the series.

Overall: 5/10
Despite my incompatibility, I still see potential on the series. I just personally can't stand the art, pacing, awkward battle scene and humor. The first half of the volume one able to makes me think that the series would be a 7 or 8 but over this short suffocating trip... I still give 5 instead of my own personal subjective 4 since i understand that the non-orthodox shounen approach might appealing for some people, but for me.... its enough for now.