A pro-tip to any aspiring writers, who may want to write for adults / young-adults --
If you have your characters react: "Ew! That's so chuuni!" -- maybe don't write that part in, like, at all?
If your characters think it's chuuni, the readers think it's chuuni too. And that includes: "Gugnir war god kick" or whatever that was, the author is full-blown chuuni, yet also has his own characters criticize it.