The term fairy tale mostly relates to older European stories that focus on children's themes.
What was your favorite fairy tale grown up ? Fairy tales do have such a rich history, probably dating back to centuries lol
Fantasy literature
Fantasy literature is literature set in an imaginary universe, often but not always without any locations, events, or people from the real world. Magic, the supernatural and magical creatures are common in many of these imaginary worlds. Fantasy literature may be directed at both children and adults. 
Fantasy is a subgenre of speculative fiction and is distinguished from the genres of science fiction and horror by the absence of scientific or macabre themes, respectively, though these genres overlap. Historically, most works of fantasy were written
tales may be distinguished from other folk narratives such as legends (which generally involve belief in the veracity of the events described) and explicit moral tales, including beast fables. The term is mainly used for stories with origins in European tradition and, at least in recent centuries, mostly relates to children's literature.
In less technical contexts, the term is also used to describe something blessed with unusual happiness, as in "fairy-tale ending" (a happy ending) or "fairy-tale romance".