what did jinwoo tried actually?

*spoiler* He was testing how much the curse's effects is affected by physical contact. Simple touching, kissing, simulated sex, and actual sex each results in different intensity of the fantasies. I think when he kissed Sangtae the fantasies in his head subsided more than if they just touched, but not totally gone as compared to if they do penetrative sex. Chapter 22 explains it

oh thank you