Timid veterinarian Yoon-seo’s life is centered on her animal clinic. Then she has a chance encounter with CEO Kang-hoon, who's her polar opposite.

After Kang-hoon fights his way out of a kidnapping, Yoon-seo finds him and reluctantly treats him at her clinic when he won't go to the hospital.

Kang-hoon wakes up in Yoon-seo’s clinic. After calling PA Kang to pick him up, he leaves the sleeping Yoon-seo his card, but her cat has other ideas.

Kang-hoon's attraction to Yoon-seo hits another hurdle when he sees her feistier side and misinterprets her bill for treating him at the clinic.

When an old rival gets under Yoon-seo's skin, she makes a rash decision about the clinic. A new business arrangement with Kang-hoon is on the table.

Yoon-seo opens her new practice. Kang-hoon gets motherly orders on dating. Two very different lunches are turning points for Kang-hoon and Yoon-seo.

Kang-hoon helps Yoon-seo show up her mean friends, then suggests a new contract to help them both. Yoon-seo and Sang-hyun have a first date.

Yoon-seo's friends give conflicting advice, while Ka-pang tries to get Kang-hoon to finish his pet food commercial. A new contract is in the works.

Yoon-seo and Kang-hoon finally sign the relationship contract, but the first day doesn't go as smoothly as they'd hoped.

Ra-mi goes to Yoon-seo's clinic, where they're openly hostile to each other. On their first fake date, Kang-hoon pretends he's annoyed by Yoon-seo.

Kang-hoon invites fake girlfriend Yoon-seo to an important party. He is stunned by how beautiful she looks, but the party takes unexpected turns.

Yoon-seo and Kang-hoon are photographed kissing at the party, causing a press frenzy. Sang-hyun and Kang-hoon argue when Yoon-seo twists her ankle.

Yoon-seo gets drunk with Sang-hyun after treating an elderly dog. Kang-hoon is furious, and the following day, Yoon-seo misinterprets what happened.

With no place to live, Yoon-seo moves into Kang-hoon's house. Being a wealthy guy's fake girlfriend has its perks, especially when lightning strikes.

After Yoon-seo moves in, Kang-hoon tries to adjust to the close quarters -- and her cat. They draw up a house agreement, but that causes more tension.

Business is booming at the clinic, leaving Yoon-seo no time for Kang-hoon. A real kiss and a visit from Kang-hoon's younger brother complicate things.

Old sibling rivalries cause even more tension between Kang-hoon and Kang-joon. A dog bite and a mysterious photograph make Yoon-seo begin to wonder.

Kang-hoon and Kang-joon have a bad case of sibling rivalry. Yoon-seo has an idea to wash away the anger, until an unexpected visitor stops them cold.

Kang-hoon's mother isn't happy about his feelings for Yoon-seo. Just when the couple seems the closest, a new contract proposal could ruin everything.

A heartfelt proposal might be the end of Kang-hoon and Yoon-seo's relationship. But is a different kind of contract an offer Yoon-seo can't refuse?