Brian is a rambunctious student from the School Assembly episode Episode 99.6. Near the beginning of the assembly Principal Michaels orders Brian to suck the staff off after school for a week to which Brian says ‘I’ve got my comeuppance’ (this punishment is later withdrawn).
Brian also points out that the whole school assembly is similar to an Aunty Donna sketch.
Brian really loved Craig Henderson’s speech about roast cauliflower (coincidentally both characters are voiced by Greg Larsen).