If I drop off one of the fans will he/she get e-mail that I am no longer a fan of him/her?

Nope, but their fan number will go down.

No, tu only get messages when someone fans you.

Their number will go down, but depending on how many fans the person has and how often they're added por people, they probably won't notice if tu drop them.

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the number will just go down like once someone faned me and didn't mean to so she unfaned me and it just went down : )