>>132861663Kindle, EBJ, etc. A couple Jump magazines get ebook releases and they're all on enough stores that you should be able to get it (WSJ being the exception).
As for Serapuchi, don't even consider importing magazines to read that, it gets literally four pages a chapter, at most. Pic related is the entire chapter in the first issue of Crown..
It gets chapters in SQ, SQ.Crown (and SQ.19 in the last issue for some reason), and the Seraph of the End website, so you could probably at least get the website ones. Pretty sure the first volume comes out in December along with the next main Seraph volume.