Probably programmer-speak ... "mutual friend" being the designated LJ term for that situation, quite likely based on the use of the term in the similar situation of friend classes in object-oriented languages like C++. Which would be why it doesn't seem odd to me. :)
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Date: 2006-12-05 09:01 am (UTC)(no subject)
Date: 2006-12-05 05:18 pm (UTC)(no subject)
Date: 2006-12-05 01:09 pm (UTC)(no subject)
Date: 2006-12-05 05:19 pm (UTC)