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1.
A secondary girlfriend, one that is around constantly and annoys you and your personal friends.
Heather - Hey can I have your boyfriends friends phone number?

Girlfriend - No, he says you are a Susan on the Sly
by JT Stranganopolis March 31, 2009
3 4

Words related to Susan on the Sly

annoy dog friend girlfriend poor grammer the bounty hunter