This is a summary based on our understanding of the series.
Please also note that this summary contains spoilers.
Jung Ji-Woo (she) works in a PR team for a large company – and there was a new addition to the team, his name is Jung Ji-Hoo (He). He is quite famous, and is being treated well by their boss since he is the manager’s son.
Ji-Hoo had a package, and Ji-Woo has claimed it mistakenly since their names sounded alike. She opened the package and found a collar and a leash. When Ji-Hoo arrived, he tried explaining that it belongs to him and it’s for his dog. When they were about to settle the incident, the box fell on the floor revealing a brochure – it turns out the leash was intended for S&M use. Ji-Hoo got embarrassed and was anxious that Ji-Woo might reveal his secret to their workmates.
When they finally talked, Ji-Woo clarified that she doesn’t have any plan to reveal his secret because it is none of her business. Ji-Hoo thanked her for it.
During one of their conversations, Ji-Woo also apologized for her attitude because she is the bossy kind. Ji-Hoo misinterpreted this – he thought Ji-Woo was telling him that she is also into S&M, that’s she’s dominant (Ji-Hoo is submissive).
Ji-Hoo asked Ji-Woo for her to become his master. Ji-Woo was hesitant at first, but she got very curious. She did her own research about S&M, also researched on how to become a master. She later on accepted to be Ji-Hoo’s master, she even prepared a contract.
They agreed to have a temporary three month relationship. They played around. Ji-Woo stepped on Ji-Hoo, she hit him with a belt, they even caused a mess while it was just the two of them in the office.
During their final play when their contract nears its end, Ji-Hoo and Ji-Woo played around, and they ended up kissing each other in bed. Ji-Woo suddenly asked to stop, saying she no longer knows what she’s doing anymore. She walked away and she avoided Ji-Hoo after that.
While they were not on speaking terms, an intern found an audio recording of Ji-Woo (it was from a pen that records audio.) The intern sent it to Ji-Woo via email asking her to be careful because others won’t understand – the intern ended up sending it to everyone in the office.
The audio recording was of Ji-Woo ordering Ji-Hoo around, saying things like “take off your belt”. They were asked to explain to their admin. During that hearing, Ji-Hoo revealed that he wants to go out to Ji-Woo.
They reconciled after that and started going out, even without the contract. They agreed to try a romantic D & S relationship.
The End of Love and Leashes Movie.