Right, hum, OK. So, first I heard that Kurts' Dad was a nobleman or Boyar somewhere in Eastern Europe, where Raven Darkholme had married him as a way of hiding out. Of course, when Kurt was born it was kind of obvious that he was a mutant, so Raven got out of Dodge, dumped the kid with a circus and made off for parts unknown.

Later, we get a retcon where Kurts' Dad is actually Azazel, who is some kind of half-mutant, half-magical type.

Then they start writing Raven as bisexual, which is fine, as she can be either male or female convincingly, so is naturally gender-fluid anyway.

Now this version of events, in which Raven, in a male form, fathers Kurt on her longtime lover, Destiny. In the context of the characters, this is acceptable. The only hole is that Kurt was represented as a young man at the same time as Destiny is presented as a very old woman! Are we to assume that Kurt, like good old MumDad, is virtually immortal and thus much older than he appears?

Also to the point someone has been making, Raven has spent most of a long life being hounded and hunted by 'normal' humans. Enough to make anybody feel uncharitable toward them, don't you think? Mystique is not a Nazi - she's one of a handful of Jews in a world full of Nazis!