Ad libitum (/ædˈlɪbᵻtəm/) is Latin for "at one's pleasure"; it is often shortened to "ad lib" (as an adjective or adverb) or "ad-lib" (as a verb or noun). Lee Seunghwa and Seo Yunha is close Seunghwa likes yunha more than a friend Yunha is crazy about seunghwa But they have to put up with the facade so called oppa and dongsaeng relationship What will happen as they realize they want more?