Romantic GP possibly wanting Eastern girl (6)
'romantic' is the definition.
'gp possibly wanting eastern girl' is the wordplay.
'gp possibly' becomes 'dr' (gp is a kind of Dr).
'wanting' says to put letters next to each other.
'eastern' becomes 'e'.
'girl' becomes 'amy'.
(Other definitions for dreamy that I've seen before include "Gorgeous (informal)", "Lovely", "wonderful", "romantic", "Fantastic".)