Every Necromundan Chaos Cult is led by a Demogogue - that forceful and charismatic (or possibly underhand and scheming) personality that persuades, coerces or tricks people into following them. The Benevolent Brothers are no different, being led by the monk-like Jakob, brother to Wilhelm the witch.
Jakob walks the mutie slums barefoot, dispensing food to the hungry and blessings to those with bruised souls. The Cult of the Benevolent Brothers supports the oppressed mutie population, and in turn muties offer the Brothers their loyalty, their ferocity and their lives in pursuit of mutant rights.
I built Jakob many months ago from a selection of parts which resulted in a pretty unusual figure with a look of a holy man. I knew that in game terms I wanted him to carry a grenade launcher, but I didn't want to ruin the simple look of the figure, so I decided to give Jakob a servant (Wretch) to carry his equipment for him (possibly there is some irony that a cult leader dedicated to mutant rights is happy to have a slave-like figure attending him).