Heroin chic is a 1990s fashion aesthetic of pale, gaunt, smudged-eyeliner models, criticised for glamorising drug use and unhealthy body images. Periodic revivals. Worth conversations about body image. If your kid uses it constantly, ask them where they first heard it, not to police their speech but to understand which online community they are in. Most slang of this kind moves through TikTok and group chats, so seeing it in your child's vocabulary just means they are plugged into normal teen internet culture.