You could feel the literal action, the fights, the sword swings, whatever, they were all performed to such a high standard it is genuinely incredible.
Things suddenly start taking a pretty macabre twist and Nezuko seemed to start losing her grasp on humanity.
While it can be a little heartbreaking or triggering, it makes it more believable in the context of the story and what they do.
Nevertheless, the series ranked 1st in 2019 Oricon's annual manga ranking chart, with over 12 million copies sold, while One Piece ranked at 2nd, with over 10.
He is a nice guy at heart, and easy to get behind which makes for a likeable protagonist, but not necessarily the most interesting to watch.
Both novels ranked 3rd and 4th respectively in Oricon's overall ranking chart.