Eun-gi'seventfullifeinaboardinghousehasbegunwiththethreeladies:asexyownerofaboardinghouse,herdaughterwhoisevensexier,andhisinnocentfirstlove.Eun-gi,afreshman,hasfoundhisnewplaceinaboardinghouseoperatedbymotheranddaughterwhenhecametoSeoultostudy.Hisonlypleasureistoplayalongintheunspokenpush-and-pullrelationshipwiththemotherorthedaughter.Oneday,hisfirstlove,Soon-yi,whoisinnocentanddocile,suddenlycomestovisithimattheboardinghouse.Withthesexydaughteroftheboardinghousebehindthedoor,andthecurvaceousladyowneroftheboardinghouseinthebathroomnexttohisroom,the20-year-oldvirginEun-gi'不眠之夜开始。
