1. This story was born from the author's resentment after a streamer was knocked flat by some inappropriate stereotypes. Also known as The Whole Process of a Shut-In Guy Breaking Out of His Shell and Rejoining Society, You Can't Handle a Battle-Worn Older (?) Man, and My Retirement Story Has Problems After All. In short, the streamer couldn't stand watching this guy flounder with a half-paralyzed language system and refuse to do anything about it, so they gave him a cheat skill in that area. Things are urgent (urgent how?), so forget about all the backstory and consequences. This poor kid won't even live to 25, so cut him some slack.
2. This story includes world-weariness, illness, weakened character portrayals, unnecessary melodrama, and pointless melancholy. The writing isn't good. I write whatever comes to mind and ramble about whatever I dream up, so it's all made up. If you can't accept that, please don't force yourself to read it. Avoid it if it's not for you.
3. This is my personal interpretation of the characters, so some out-of-character moments are inevitable. If you feel uncomfortable while reading, stop immediately.
4. Original minor characters appear.
5. This is probably a character-focused story with no romance. Within that, it respects all the pairings implied in the original work, but Tanjiro and the others are an exception. They're still kids, after all. That's just the author's personal preference. Rather than watching them have clearly defined, exclusive romantic relationships (I'm just pessimistic enough to think love and friendship can't be perfectly balanced), I'd rather see them live together forever in a warm, more-than-friends kind of way. I guess that breaks up the canon pairings, so why are you still reading? Run away! (Pointing.)
Theme: Overcome hardship and learn to accept yourself.