Who is Nick Bamba from The Cat Who Went Underground and what is their importance?

Nick Bamba is one of Qwill's friends. He recommends Clem Cottle when Qwill is searching for a carpenter to build an addition to his cabin. Nick also spends the night at the cabin to protect Qwill when troublemakers plot against him. When Nick follows Koko into the crawlspace, he discovers Joanna's list of murder victims.