A bro that bro'ed before all other bros. The prototype for all future bros. Does not know how to get anywhere other than the gym and tanning salon. One cannot bro harder than the protobro. Typically they dwell in Omaha, Nebraska and can be easily distracted by other bros.
William Anderson must be the proto-bro... he broes so hard motha fuckers try to fine him.
by Bromaster420 July 23, 2016
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