When two people receive a boner at the same time for the same reason.
boy friend: "So I friggin' got a boner for a picture my girl friend sent me last night!"

best friend: "No shit?! I'm afraid I have bad news! I received the same picture last night . . . and the same happened to me. I hate to break it to you bro, but we are boner brothers!"

boy friend: "Son of a bitch whore!!"
by Adrian "the shiz" October 18, 2009
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