I know that this may come as a surprise to you that I'm writing a Märchen-based theory, when a lot of my ideas generally come from the doujin-era of Sound Horizon. That's not to say that I don't enjoy the newer releases, I just don't often find a way to express new ideas, especially with Märchen of all things, with so many unique takes already existing. With that out of the way, I'd like to give the reminder that I'm not considering invalid anyone who disagrees with me. Feel free to make any counter-points!

Within the story of Märchen, we hear the line of Bluebeard not forgiving anyone who judged someone in his past as a witch. Naturally, one may consider that this is related to the events of IdoIdo, especially with Therese having a rather blue palette and Bluebeard having, well... A blue beard. If you look a bit harder, that's where the similarities end. März doesn't exactly look anything like him, nor does he show any similar personality traits. Elise? Well, sure, but never März, even as Märchen.

No, my theory has nothing at all to do with Bluebeard. The Marquess has a lot worth discussing, but not when I entertain the idea of März' father. (His quotes are actually arguably about Jeanne d'Arc, but that's for another day) Actually to find the father, we need to look back to Roman. I'm going to attempt to affirm his father is none other than Auguste Laurant. Tenshi no Chouzou helps paint the picture a lot clearer, but to truly understand this, we need to expand our understanding towards Therese.

Within Kanojo ga Majo ni natta Riyuu, we learn that Therese is both a Sister and a Mother. Of course, we understand the meaning of mother is in this case, but we don't exactly have a clear understanding of what Sister is meant to mean. I understand that a general consensus usually involves around incest in this case, but let's take things to a religious perspective here, after all we do see about 77 crosses on the cover.

Christendom is actually quite complex, with so many different variations of such, but today we will be looking at the Catholic scale of things, since the other major sect, Protestantism, has little relevance with this term. Of course, in Catholicism, a nun is referred to as a Sister, with a preacher referred to as a Father. It does get even more complex, however. There is another ranking in Catholicism simply called a "Sister". The major difference would be that a nun would generally live within a monastery, which is often cloistered. However, that is not always the case. Why is this relevant?

If a nun were to get impregnated, even in 2015, they would be kicked out of their order effective immediately, minus in more extreme cases that I don't want to get into. This is done today, mind you. The punishment wasn't very forgiving in what's essentially the Dark Ages. Another hint about this correlation comes in the three vows: poverty, celibacy, and obedience. In short, if this holds any merit, Therese would have taken these solemn vows (simple vows were not introduced until recently, they can be disregarded), which meant she would have to give up her belongings that fit the temporal, or items that were not of religious significance. Therese was a noble, and she has little to show for it in IdoIdo. Why would Therese be in the church, despite being a noble?

She would be considered as an oblate, in this case. As in, her family would have given her to the church (most of the time this was willing). Considering that her "powers" are in line with what would be considered as a seventh daughter of a seventh daughter. Since the 7th horizon loves the idea of 7, it isn't the worst possible explanation as to how she can handle such concepts, and this concept exists beyond Christendom and into the ideals and spirituality of witchcraft. There is a duality with this concept, where one could be seen as either good, or as evil.

I know that I'm throwing out a massive amount of info, with little about the father.

*There's no draft feature, will finish later*