Character: Raven
Race: Svirfneblin (actually a half gnome, half shadar-kai, in a world where Shadar-kai are descended from Mordred and his patron, The Morrigan)
Patron: Herself, using an ancient ritual stolen from the memory of Muninn, Odin's raven. She hung from the Tree of Life, in the Otherworld, for 9 days, stabbed with her own spear, a sacrifice, herself to her own self given.
Boon: A divine raven named Coal, who remembers her dreams for her, and helps her decipher the secrets held within them, to unlock new power. (Tome, with her Familiar acting as the Grimoire).
What does she want? Her greater self, the becoming goddess, wants her to grow, learn, and ascend. She also warns herself, in her dreams, that if she strays too far from who she was, she will lose herself entirely, and become a dark power with no humanity, or memory of humanity. OTOH, since true names have power over creatures such as she is becoming, she cannot use her true name.
Character: Nicodemus
Human, 1920's-30's Earth
Patron: Pieli, the watcher in the mirror, eater of childhood, darkness in the deep water, First God of The Terror In The Unclearly Seen Reflection.
Boon: Arcane sigils covering Nico's body give accomplish two things, one intnetional and one accidental. First, they act as one of three seals on the prison of Pieli. Second, they accidentally became a two way channel by which Pieli's power is made available to Nico, and through which Pieli can sometimes taunt the warlock, whisper dreadful temptation into his ear, or lead his true followers to find Nico and the two other Seals to seek their end if they won't turn to Pieli's service.
The tattoos act as a Grimoire (tome), granting Nico much more powerful ritual magic than he'd otherwise have, and helping him in binding and summoning spells, ranging from making the dead speak, to turning invisible or seeing in total darkness.
What it wants: Like all of the First Gods, Pieli wants to consume, destroy, to bath in entropy made manifest. Pieli in particular is a creature of madness, fear, and the corrupt hunger of healthy desires twisted into broken and sharp edged things. Nico and his two closest friends and sometime lovers, Appo and Sera, found Pieli in the woods of southern Finland in the fall of 1917 (IIRC), when they were 13. The meeting nearly broke them, but they escaped, and found comfort in eachother. They also studied the occult, and became accomplished warlocks.
Years later, during World War 2, the three returned to that forest when they learned that Nazi occultists were attempting to free Pieli as part of a desperate attempt to turn the First God against the Soviet army. For a long winter, they hunted Nazis in the woods, binding the power of their deaths into a slowly building ritual of imprisonment, culminating in a final ritual at the pond where they first found the dark god as children.
The ritual worked, but because of attempted interference from someone they thought they could trust, who was in fact a cultist of Pieli and sought to invert their ritual to fully free the creature, they had to mark the three seals of the ritual upon their own flesh, and place themselves into the circle of the ritual in order to close the circle and complete the binding.
They cannot spend extended periods together without Pieli's voice growing louder in their minds, and it's cultists finding them, they cannot age, they cannot stay in one place for more than a few years, and they cannot end their unnaturally extended lives without freeing Pieli.
They discovered these dangers the hard way, when they had to abandon the family they had started together, giving their children (3 girls, 1 boy. The boy and one girl from Nico, the other two from Appo, with Sera as mother to all four) to distant relatives for their safety, and only coming together again once every 9 years to take council, check on the binding, and compare notes. For they still hope that they can bring themselves out of the binding magic, place the seals onto objects and seal them away, and either live out a normal life or simply find rest at last.