I totally get the struggle of hunting down specific chapters! For 'chapter 25' of any series, I usually start by checking official platforms first—like the publisher's website or apps like Shonen Jump Plus for manga, or Kindle Unlimited for novels. Sometimes, authors or scanlation groups drop links on their Twitter or Discord servers too.
If it’s a niche title, forums like Reddit’s r/manga or r/lightnovels can be goldmines for fan-translated stuff, though I always feel iffy about pirated content. My personal rule? If I love a series, I try to support the creators by buying the official release once it’s available. The thrill of finding that one missing chapter is real, though!