This story features a controllable transformation system.
The protagonist, Wensley Fauce, can change between male and female and, at least in the early stages, can decide which gender to stay in based on his own will. Think of the style closer to a "Blood Princess / Dragon Princess" type of transformation, not a half-beast elf or fox form.
However, this full freedom only exists in the early to mid story.
Whether the transformation remains completely controllable later on, becomes one-way, or is affected by plot events is part of the mystery and character development. If the idea of a gender-shifting main character whose situation may change over time bothers you, please consider this your warning and feel free to skip this book.
Also, please be aware of the romantic focus:
The female form of the protagonist has a very strong presence and will eventually take up most of the "screen time".
The main emotional and romantic storylines revolve around the protagonist's female identity.
The relationships and flirting are overwhelmingly girls' love (yuri). Even though Wensley starts as a "villain young master," the core of this novel is about women loving women, with the plot, system, and transformation all serving that direction.
If you dislike gender transformation, yuri, or a male-soul protagonist spending a lot of time in a female body and being treated as a woman by the world, this may be not for you.
Early chapters are more descriptive and focus on worldbuilding. Also, unlike other books where the transformation happens immediately, Wensley's transformation appears a few chapters later, after his "doomed villain" setup.
Thank you for you're time and have fun reading :)