What it means
Used for someone or something that looks amazing but doesn’t offer much else. Think a model-level cast, flashy visuals, a car with all the trim, or a shop display that’s doing the most in real life too. It’s a compliment for the eyes, with a little side-eye that the substance might be thin. Nice to look at, not always worth the hype.
Usage examples
"That new series is pure eye candy, mate. Everyone’s unreal and the shots are peng, but the storyline’s so waffly I was lost by episode two."
"The advert is all eye candy, gorgeous beaches and shiny cars, but it never tells you what they're actually selling."
"He's lovely eye candy at the party, but ask him a question and the lights are on with nobody home."
"Yeah, the game's proper eye candy, but once the pretty lighting wears off, there's not much to do."
"That restaurant's all eye candy on Instagram. Cute plates, neon signs, tiny portions, vibes doing overtime."
Where it comes from
It’s been around in American English since at least the 1970s, built from the plain idea of candy for your eyes. People first used it for attractive women and glossy visuals, then it spread wider to films, design, cars, games, and anything that looks lush but might not have much going on underneath.