I believe that masturbation and fantasies are a matter for you, your head and your hand. I would not want to label any fantasy as 'wrong' since they rarely reflect on any real life feelings towards your partner.

Attaching guilt to fantasies is probably very unhealthy, however being aware that certain fantasies should always remain in that realm is healthy, sensible and moral.

__________________
"Time flies like an arrow -
Fruit flies like a banana"

M Y - N A U G H T Y - P I C T U R E S ! !