The creation of a false MSN Messenger account with the purpose of pretending to be a hot chick to pull a joke on a friend by pretending to chat them up. Usually results in the object coming into school bragging about thier online achievements whilst people lulz quietly around them.

Name originates from the very first one created by school children, sexibexi@live.com.
George and Greg so totally set Richie up on MSN yesterday. They made the best Sexi Bexi ever.
by L05 June 24, 2009
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becca is hot yet, thinks she's not... i would put a photo but then she'll cry...
by jamie loch March 09, 2005
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