>>283012906
Attractive characters (thanks to MAPPA) + non-stop action without fleshed out character relationships + its character centric approach to action and fighting where character powers are stand-ins for their personalities + the setting is basically today's world + its approach to plot development where it's always half-assed and underdeveloped so people find it compelling to jump in and complete the blanks by themselves

It's the type of shonen someone who is very concerned with himself would write, which means it's not a lot like usual shonen at all, and the author can't help but show favoritism at every step when it's the sort of work where he absolutely shouldn't, it's closer to a shoujo in that aspect (and JJK0 is basically Geto and Gojo fighting over Yuta as if it was some otome game). Hidden Inventory arc is very good fiction in my opinion though Toji vs Geto is pretty bad.