"Who needs lips?" Bertin is a former childhood tutor of Aloysius and Diogenes Pendergast. He taught natural history and zoology officially, but was also steeped in the local lore and legends of New Orleans, including the arts of Vôdou and Obeah. Aloysius referred to him as maître, while Cornelia Pendergast regarded him as being the most scandalous of the Rochenoire staff. Bertin is easily agitated, and in extreme instances requires a concoction he calls "sipping syrup", consisting of lemon-lime soda, vodka, codeine in solution, and a watermelon-flavored Jolly Rancher candy.