Rule #1: Don't add random numbers to the group chat. Rule #2: If you do...maybe make sure they're not secretly famous. After a failed attempt to add someone they met once (and barely remember), Jayeon, Gowon, and Bohyun accidentally add a guy named Ryul instead, except they don't know his name at first. He's weirdly funny. Suspiciously busy. And somehow always online at 2 a.m. They keep him. What they don't know? Ryul is actually a famous idol-and now his members are getting involved too. Between chaos, secrets, and way too many messages, Jayeon finds herself falling for someone she's never even met. But in a story that started with the wrong number... what happens when the truth finally hits "send"?