Henri's greatest moment of pride in his mortal life was being named to Papa Doc's elite guard, the Ton Ton Macoutes, which he served in until the dictator died. Ten years of that time were also spent as a ghoul of Legba's childe, Jean-Paul. When the elder Serpent ordered him to send reinforcements to New Orleans, rather than deprive himself of one of his current childer, Jean-Paul instead Embraced the psychopathic ghoul and sent him. While the decision to do this was purely self-serving, it worked out well for both Legba and Henri. Particularly after Papa Doc was forced to flee to France and the country was taken over by Henri's cousin, Jean Bertrand. There is still an arrest warrent for the butcher Henri once was.
His Embrace elevated him to a whole new level, opening the possibilities for new cruelties in the service of his new lord. Never one to pass up the chance to inflict pain or suffering, Henri happily complied with the orders given him by Legba. His loyalty was assured by his one spiritual indulgence -- a strong faith in voodoo. During the past twenty-five years he has made a reputation for himself among the kindred of New Orleans as a vicious lapdog of the Serpents, sent against their most hated enemies or their most negligent pawns.
Henri is a sociopath with a borderline obsession with voodoo that has been encouraged and reinforced with disciplines in order to make him easier to manage. As with many secondary psychopaths, he has underdeveloped social skills, poor impulse control, and a natural cruelty. He is easily bored and tends to provoke violence merely as a way to amuse himself. The bulk of his excesses have been kept under wraps by the Serpents, but many are growing tired of dealing with him.
Henri is properly respectful of Legba, as a loa incarnate, and does as Paris tells him to, because Legba has decreed it. Everyone else is pretty much on their own except those, like Marie, who openly practice voodoo. They get his respect and this fact has been used by Marie and the others to try and use him for their own ends. He is too devoted to Legba, however, to be used in any sort of coup. There are hopes, though, that when the elder returns to Haiti, he'll take Henri with him.
Henri pays little heed to the other kindred, except when set upon them by the elder. He has, on several occasions, butted heads with the Brujah in his street operations and there is little love lost between them.
Henri is the one sent by the Setites to collect on debts and oversee the base street crime they encourage and manipulate. As such, he has a reputation on the streets and anyone who is involved in New Orleans crime has heard of 'The Haitian' and will do their best to avoid meeting him. Henri has expanded what he was given since he's been here and is running a collection racket that rivals the Mafia's (and, unfortunately, La Cosa Nostra is too weakened, at current, to oppose him).