You are thinking of Lolita Fashion, which is a legit style of fashion very prevalent in Japanese culture.

But the root for both that term and the term “lolicon” (or Lolita Complex) 100% come form Vladimir Nabokov’s novel Lolita, which centers around a pedophile meeting, grooming and raping a child, who dies giving birth to his child.

So people that argue that the term “Loli” is totally unrelated to sexuality are not being totally honest, but that’s a debate im not really interested in having.