The Lost Twin
The Huldufolk are powerful, supernatural beings, with a tremendous amount of control over the world. But they are very much like us, and like us, the Huldufolk crave what they can’t have. The Huldufolk live among humans, can move among us and influence humanity, but they can never truly be a part of humanity, and it is impossible for them to ever truly be understood by a human (unless they do something terrible to bring them closer than they should — see The Stolen). Still, because the Huldufolk are very much like us, they still manage to fall in love with the humans they walk among, and sometimes humans manage to love them back, even if they don’t truly know what they love.
When a Huldufolk and a human have children, they always have two: one human, one Huldufolk. The Lost Twin. Once conceived, the Huldufolk parent can never appear to their lover as the same person, no matter what happens to the children. If the children are born to a human mother, twins are born in the hospital, and one is quickly forgotten about, disappearing from all records and all human memory. If the children are born to a Huldufolk mother, the father will usually receive a basket with a baby one day, along with a mysterious note of explanation.
In most circumstances, the human parent raises both children — even though they don’t realize it. The human child will probably often talk about having a play companion, but the adults of course write it off as kids and their imaginary friends. Once the children are old enough, the Huldufolk parent will spend more and more time with their child (either remaining invisible, or appearing as babysitters or new family friends), and will start teaching their Lost Twin more about their secret world. Even with this introduction, the Lost Twin is firmly planted in two worlds, forever torn between them, and rarely leaves their twin’s side for very long.
Advantages: Because a Lost Twin grows up alongside their mortal twin, they have much better understanding of the human world and its workings than the Hidden Born, and therefore have an easier time influencing and shaping that world.
In addition, when a Huldufolk’s mortal twin is asleep, they can appear to the world as their twin, taking on their appearance (whatever minor differences there might be) and persona in the mortal world. They can do this with significantly less effort than a Huldufolk would normally be able to appear as someone among humanity.
There’s another, darker advantage available, for any Lost Twin who is amoral enough to follow through on it, and willing to join The Banished: if a Huldufolk kills their Lost Twin, but keeps the death secret, they can take over their dead twin’s life, freely appearing to the human world as their twin any time they wish. Most Lost Twins would never consider such a vile act, but for some who grow tired of the burden of their mortal sibling, this exit strategy is a gnawing temptation in the back of their mind.
Disadvantage: Lost Twins have a blind spot of their own: their twin. A Lost Twin spends much of their time watching over their human twin, as a sort of guardian angel. This can easily distract from their other pursuits in Huldufolk society. Additionally, other Huldufolk will often use this weakness to their advantage, causing problems for another Huldufolk’s twin so they can move against their rivals while they’re distracted.
There are two main reasons to play a Lost Twin: because you want a character story closely entwined with the continuing fate of a mortal non-player character; because you want to give other players a clear way to mess with you. If you choose to play a Lost Twin, do so with the understanding that you are giving your fellow players a clear target to cause conflict for your character — you’re giving them fragile things to mess with, to make your story better.