A few short notes on why I chose to use male protagonists and antagonists in my Los Nefilim series, and maybe a few historical facts that not many people know. There are women in the novel, as well, and I adore writing them, because they’re all so vicious (Carme, Sofia, and the Corvo twins to name a few).
The thing is, though, the books originally started with Guillermo as the protagonist. As I became more involved with different people online, I realized that my novel with Guillermo, Diago, and Miquel followed every terrible trope out there. In my case, multiple rejections became a second chance.
I considered flipping the genders and making them all women. Then I spent some time studying the various time periods. As I did, I found that laws against homosexuality were generally written against men, going back to the Visigothic Code, which specifically addressed sodomy and no other form of same-sex love. The code itself states that anyone accused of sodomy “not only suffer emasculation, but also the penalty prescribed by ecclesiastical decree for such offences.”  Ecclesiastical decrees during the 13th century dictated the death penalty for sodomy. 
Women, on the other hand, were (and quite often still are) seen under the false assumptions that they are either: a) naturally affectionate or b) not in control of their own desires. There is the added perspective that, seen through the male gaze, f/f copulation can be arousing to males, and therefore less likely to be seen as a punishable offence.
Regardless of the reasoning, as time moved on, the persecution against gay men remained in place. It wasn’t until the early 20th century that both psychologists and physicians began to study sex and gender associations more openly. One of the most renowned was Dr. Magnus Hirschfeld, a German physician who founded the Scientific-Humanitarian Committee, which pioneered “the first advocacy for homosexual and transgender rights.” 
Hirschfeld believed that "homosexuality was part of the plan of nature and creation" like other forms of love and affection. In 1919, he co-wrote and acted in the film Anders als die Andern ("Different From the Others"). Conrad Veidt, a prominent German actor who makes a cameo in Where Oblivion Lives, played one of the first homosexual characters ever written for cinema in this film. Because of this, he is Rudi Grier’s hero.
Hirschfeld, for his part, uses his role to play himself and makes an attempt to educate his audience. A portion of the film is devoted to Hirschfeld testifying in court that “the persecution of homosexuals belongs to the same sad chapter of history in which the persecutions of witches and heretics is inscribed."
Unfortunately, Hirschfeld became a Nazi target in the early 1930s. He escaped arrest only because he was on a book tour when the library at Hirschfeld's Institut für Sexualwissenschaft (Institute of Sexology) was raided on 10 May 1933. The Nazis burned thousands of books.
In Spain, France, and Germany (where the majority of the Los Nefilim series takes place), police kept lists of known homosexuals. Pierre Seel, a young Frenchman, frequented Steinbach Square in Alsace, which was a place where men went to meet for sexual encounters. Unfortunately for him, he one day lost a treasured watch to a thief. He went to a police station to report the theft and found himself on the receiving end of a lecture from the detective. Seel didn’t know for certain, but based on later action by the Gestapo, he realized the detective must have placed his name on a list of known homosexuals. 
In Germany, these were known as "Pink Lists." When the Nazis seized power, they rounded up these men and told them to report to Gestapo headquarters. Seventeen year old Pierre Seel was likewise summoned by the Gestapo to be interred in a concentration camp.
After the murder of Ernst Röhm, the laws against homosexuality (women were still exempt) became stricter. The obsessively homophobic Heinrich Himmler had the Gestapo step up their raids. In 1937, he told SS leaders that “it was regrettable that gay men could not be killed, but at least they could be detained.” 
According to Richard Plant, in his book, The Pink Triangle, between the years 1933-1944 between 50,000 to 63,000 men, 4,000 of whom were juveniles, were convicted of homosexuality under Germany’s infamous Paragraph 175.  Forced to wear a pink triangle, these men were detained in the concentration camps and suffered harsh treatment from both the guards and the inmates.
While German law required consent for castration, several gay men were castrated against their will. In order to “cure” the men of their homosexuality, men wearing the pink triangle were forced into particularly hard labor. They were often isolated in separate barracks, where they were forced to sleep with the lights on and their hands above the blankets at all times.
At the end of World War II, gay men were prohibited from seeking reparations for their time in the concentration camps, because homosexuality was still against the law. The laws in most countries didn't change until the mid- to late-60s. Even then many men were too ashamed to come forward. Where the Nazis failed to kill them, society turned them into pariahs. Some, such as Pierre Seel, married and forced themselves into heterosexual marriages. (Seel's ended in divorce.)
In spite of numerous books and studies of the holocaust, I was able to find only three or four books devoted entirely to the men who wore the pink triangle (these are just the ones that I’ve read):
Herger, Heinz [trans. by David Fernbach]. The men with the pink triangle: the true, life-and-death story of homosexuals in the Nazi death camps. Los Angeles: Alyson Books, 1980.
Plant, Richard. The pink triangle: the Nazi war against homosexuals. New York: Henry Holt, 1988.
Seel, Pierre. I, Pierre Seel, deported homosexual. New York: Basic Books, 1995.
So what does all of this have to do with Los Nefilim?
Well, it all sort of goes back to my decision to do things differently with the original story. You see, Guillermo started as the protagonist for the Los Nefilim world, but the more I wrote, the more I realized this was Diago’s story. If I changed his gender, then I cheated him of his story, one that has been little more than a footnote in most history books.
Writing Los Nefilim from a woman's point of view would have drastically changed the characters' perception of the rapidly changing world. By keeping the male point of view in these books, I can balance Miquel’s hope for a more tolerant world with Diago’s pragmatism. Later, in Where Oblivion Lives, Diago's actions with a young German man take on more poignancy because both must remain hidden from the other for different reasons.
More than anything, I want to show you what Hirschfeld wanted to show his audience with Anders als die Andern ("Different From the Others"). That is why my cast is predominantly male.
If you're looking for kick-ass women, I can direct you to a ton of good books, but I'm keeping my boys, because they have a story to tell, too. It begins in 1931 in Barcelona, in a novella called In Midnight’s Silence …
 FLAVIUS EGICA, KING. Book III, Title V, Section VI. Concerning Sodomy, and the Manner in which the Law should be Enforced.
 Michael Goodrich Ph.D. (1976) Sodomy in Medieval Secular Law, Journal of Homosexuality, 1:3, 295-302.
 Goltz, Dustin. "Lesbian, Gay, Bisexual, Transgender, and Queer Movements", In Lind, Amy; Brzuzy, Stephanie (eds.). Battleground: Women, Gender, and Sexuality: Volume 2. Greenwood Publishing Group: Westport, CT, 2008.
 Seel, Pierre. I, Pierre Seel, deported homosexual. New York: Basic Books, 1995.
 Wachsmann, Nikolaus. KL: a history of the Nazi concentration camps. New York: Farrar, Straus and Giroux, 2016.
 Plant also notes that six lesbians were arrested, which is considered a "bewildering statistic, since sex between women was not against the law."