Honestly, at least in the west, I think the viral meme drew a lot of attention to the manga and the decent art & premise got people to want to see where the story goes. I’m curious what Japanese readers think of Kagurabachi so far.
It's constantly in double digits in Shonen Jump rankings (for example, 17th place last three weeks in a row) so I assume it's not very popular in Japan. Normally, it would be on its way to getting cancelled bu maybe because it's very popular on Manga Plus they're keeping it as there's clearly a potential for worldwide hit there. I'm really curious to see how this situation develops (if I were to choose, I would just movie it to ShoneJump+).
