Chume

Chume is an internet slang term used to refer to someone who is acting dishonestly, insincere, or fake. It is often used to describe individuals who pretend to be one way online but are completely different in person.

Examples:
1. I thought she was my friend, but she turned out to be such a chume. She always posts nice comments on my pictures, but in reality, she talks behind my back.
2. That guy claims to be a successful entrepreneur on social media, but everyone knows he’s just a chume. He constantly brags about his wealth, but in reality, he still lives with his parents and doesn’t even have a job.