From Longman Dictionary of Contemporary Englishfairytalefai‧ry‧tale /ˈfeəriteɪl $ ˈferi-/ adjective [only before noun] HAPPYextremely happy, lucky etc in a way that usually only happens in children’s stories a fairytale romance The kiss was a fairytale ending to the evening.
Examples from the Corpus
fairytale• Their fairytale marriage turned into a nightmare.fairytale ending• And a fairytale ending ... Speilberg's latest film to aid children's hospital.