It's not too complicated. You just need a stable internet connection and a website that offers such manga. Some sites may require registration or a subscription.
It could be a very interesting novel. Maybe it's about a villainess who has reached an extremely high level in terms of her 'villainy'. She might have extraordinary powers or schemes at level 99. For example, she could be manipulating the entire kingdom's politics or be in a fierce rivalry with the protagonist.
The 'villainess level 99 novel' might revolve around a complex character, a villainess. She could be in a world of nobles, magic or some other fictional setting. Her level 99 status could imply that she has mastered all kinds of villainous tactics. She might be constantly in conflict with the protagonist or other characters. There could be a backstory about how she became such a high - level villainess, like maybe she was wronged in the past and is now seeking revenge in a rather extreme way. There could also be a love interest who tries to change her or is drawn to her despite her villainous nature.
First, you need to come up with a unique and interesting character design for the villainess. Make her have complex motivations and personality traits. Also, think of a captivating plot that keeps readers engaged.
Well, 'A Villainess for the Tyrant' manga is appealing because it offers a fresh take on the typical romance tropes. The world-building is also quite impressive and draws you in.
Since I haven't read the novel, I can't say for sure. But typically, there would be the villainess herself. There might also be a hero or heroine who opposes her. And there could be side characters like her servants, allies or enemies in her villainous plans.