I suspect Dark Candidates were a result of that uncontrolled evil energy left behind after Dracula's demise. So upon his death, most of his evil was sealed away except for his castle' in the eclipse. Even though the Demon castle (That's the real name of Dracula's castle.) is sealed in the moon's eclipse, it is none the less still unleashing and leaking evil (think about the past games, before his return, evil slowly creeps up again because of the castle), but to a much minor degree now that it's trapped up there. I think the Castle is the source of power of the Dark Candidates, attracted to their own evil hearts. Sorta like it's calling for a new Master, much like it called for Soma.
@koutei Reincarnation is taken seriously by many religions and cults, including Christianity, Judaism, and even some Wicks. Also, some scientists are fascinated with it themselves because there has been evidence of such things occurring. There has also been a discoveries related to telepathy. Overall, it's up to an individual to judge in what they believe, but don't laugh at persons face who does believe it, you don't want to insult people unintentionally.
Also, I will explain the biggest reason people can't seem remember past lives, even if you are reincarnated in a new body. If you are a newborn child, all those memories will most likely fade and disappear. A baby's brain is not a fully functioning brain in that it's incapable of remembering most things it encounters, and it depends on short term memory. So when you have a lifetime's worth of memories, they will simply fade within the course of a year or two in a newborn. However, this doesn't always turn out the case. A few people have remarkable long term memories. People like me can remember as young as the age of 2 very clearly (though I do have at least one memory of when I was a newborn, which is also rare, but not really that clear.) While other have shown themselves capable of remembering some alarming details on their youngest age, such as actually coming out of the womb.