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During World War II British spies would sometimes use semen to write secret messages on paper, as it was invisible except with a black light, which were not common back then. The term now applies to cumming on a girl and writing a secret message with it on her using your dick.
Man, I can't wait to take this girl home and give her a British secret message.
by goldencalculatortodivide February 06, 2013
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