I have no idea. Maybe you could look for reviews or comments from other manga readers who might have more insight into whether Fermat's Cuisine is a BL manga or not.
I'm not entirely sure as I haven't read it specifically. But generally, it might involve a story about a person who has the power or ability to create a king. It could be full of political intrigue, power struggles, and the journey of the main character in shaping the future of a kingdom.
The antagonists can also be popular in King's Maker fanfic. They create conflict and obstacles for the main characters, and their motives and backstories can be explored in more depth in fan - created stories. For example, a power - hungry noble who will stop at nothing to gain more influence.
One popular 'king's maker fanfiction' might be those that explore the power dynamics between the king - maker and the king. For example, stories where the king - maker has to make difficult decisions to protect the king they've helped rise to power.
Well, the king - maker is obviously a main character. They are the ones with the power to influence who becomes king. And of course, the king or the potential king is also a main character. Their relationship is at the core of most of these stories.