Brambles agreed to accompany Penny to a film screening (where he embarrassed her). In return, Penny agreed to come to Brambles' birthday party.
Also, both Brambles and his cousin Emmer were beaten up (in two different incidents) by street toughs. Emmer asked Brambles to go to the cops to report the incident, to add weight to his "anti-goblin violence" theory. Brambles wasn't really into this idea, preferring to put the incident behind him.
Later, Brambles' friend Craig came to him and confessed that he had beaten up a goblin, and told Brambles he was afraid that he might have anti-goblin tendencies. Brambles wasn't really down with this, either.