Orphanedataveryyoungage,Gui,afourth-yearengineeringstudent,hashadtoworkhardandearnforhimselfforaslongashecanremember.Still,throughthetestoftime,hestillhasasoftdemeanorandasmileonhisface.Solo,afreshmanintheFacultyofMusic,cangetanythinghewantswithaflickofhiswrist.Money,fame,goodlooks,theboyhaseverything,excepthissmile.WhenSolo'smotherpassedaway,shetookwithhimhissmile.Nothingcouldfillthismissingholeinhim...thatis—untilonedaywhenheseesasmilingboyworkingatacafe.Onenightthetwoworldscollideinasmallcoffeeshop.Foracupofhotmilkandawarmsmile,Solofindshimselfbackinthecafeeverynight.Forasoftboywhoremindshimofahusky,Guifindshimselfwaitingforalate-nightvisitorwithacupofhotmilk,nightafternight.Nightafternight,thetwoboyscontinuetomeet.Atthesamespot,atthesametime,untiltheysooncometorealizethattheyhavebecomeeachother'sbreath.Anecessity.JustlikeOxygen.