Computer science major Chu Sangwoo (Park Jaechan) is the embodiment of an inflexible and strict rule-abiding person. While working on a liberal arts group project with freeloaders who don't put in any effort, Sangwoo decides to remove their names from the final presentation. But he didn't imagine how involved he would become with the person whose plans to study abroad were messed up because of that project.

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The involved person Jang Jaeyoung (Park Seoham), a design major, is Chu Sangwoo’s polar opposite. He is stylish, fun-loving, and above all -extraordinarily popular-, except for one big problem, Chu Sangwoo.

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What happens when an engineer and an artist whose personalities are like oil and water, have to work together? Jaeyoung is like a semantic error in the perfect world of Sang-woo. Will Sangwoo be able to debug this?