Improper Workplace Relationship

A coworker I was kind of seeing— found out a secret I didn’t want anyone to discover. “I’ll give you more. Anything you want. If that’s how it’s going to be… then just sleep with me.” A workplace contract relationship that started from a misunderstanding. I thought he’d have the same goal as any other guy, but… this man says he’s curious about me. If it’s supposed to be just a physical relationship, why is he so good to me? Why is he curious about me? And why am I starting to want more, too? This improper affair… Is it really okay?