I would most certainly use it as a first name for a girl, and as a middle name, too. It just sounds so soft and wispy and ultimately feminine that it would make the perfect girls name.
As for what first and middle names to put with it, here are some that I like:
Afton
JustineAfton
ChristinaAfton
GeorgiaAfton
LauraAfton
MyfanwyAfton
HelenaAfton
VictoriaAfton
FionaAfton
SofiaAfton
MargaretAfton
HeatherAfton
KittyAfton
RosabelAfton
LuanaAfton
BenedicteAfton
WilhelminaAfton
BeatriceAfton
HeidiAfton
CharlotteAfton
LouiseAfton
CecilyAfton
JaneAfton
Ines
Tess Afton
Eleanor Afton
Sybella Afton
Lucy Afton
Lily Afton
Beatrice Afton
Molly Afton
Julie Afton
Liv Afton
Fiona Afton
Elizabeth Afton
Sybilla Afton