Junkoku no Alpha

Junkoku no Alpha summary:

The French Revolution, which started with the king, sent many citizens to the guillotine, "exporting" the momentum of democratization to countries around the world - marking a turning point in history.
But underneath the surface, there was another world that none were aware of...
18th century France - this was a time where the world's royalty, nobility, and commoners were separated into a 3-tier system, α (alpha), β (beta), and Ω (omega).
King Louis XVI was known as the "dim-witted α." Queen Marie Antoinette, who married in from a neighboring country in a political marriage, was ridiculed as the "lustful Ω."
Then there was a certain girl who held a grudge against the royal family...
Seeking, hating, deceiving... A swirling conspiracy emerged, catching everyone in a revolutionary storm!