Klaus is the head butler of the Sanzen'in family, who is usually away on business. He has a low alcohol tolerance, doesn't do well with tobacco or women, and likes cars and bikes. He distrusted and disliked Hayate because he was suppose to find Himegami's replacement himself. He challenges Hayate often where the losing condition would be Hayate getting fired. He eventually becomes a rather obscure entity only appearing every 30 or so chapters to explain his distaste in being forgotten.