The pacing in this manga is so fucking dull it's actually impressive.
Every enemy that appears is instantly defeated; every mystery that comes up is instantly solved; every time the protagonists run out of something to do, something new "just happens" to be happening; time itself doesn't seem to exist at all.
You know how in a typical narrative the tension is supposed to rise then fall as it's resolved? Here's it's a complete flatline.
It's dead, Jim.