Lazy Sigh of the Villainess

Lazy Sigh of the Villainess is a reincarnation isekai. A young Japanese woman is reincarnated into the Crystal Labrynth otome game. Unfortunately its as the villainess, Eseria Shugren; luckily its as a child, giving her plenty of time to bulild a good reputation.

Finding the world to be utterly BORING with little in the way of entertainment, Eseria takes it upon herself to recreate games from Earth and even creating light novels; all under the personal doctrine of "having fun is justice". Eseria partners with the Wallace company owner, befriending his son, Cole, who undertands her designs better. Unfortunately, Eseria ends up betrothed to the first prince soon after; due to her reputation as a revolutionary game creator piquing the interest of his mother.

Trivia

 * The manga opens with Eseria going through what should be a condemnation event; though she doesnt care. Even if the prince tries to paint her as a wicked person, she has plenty of character references from her family and friends.
 * Plus he is shown to be openly condescending and hostile to her throughout the years; when Eseria is actually polite and even just ignores him.
 * Eseria writes light novels based on Crystal Labrynth due to literature in her new world lacking anything simple and fun like a story book. Though its not stated if she writes them based on each capture target; with the names changed, to avoid suspicion.
 * Eseria has a personal fortune build up from getting 10% of all sales of games and light novels.
 * Even if she never marries nobility, Eseria can make a living off her contributions.
 * By chapter three, Eseria has created Reversi, Kondoma, Stray Life and light novels. She is also working on BL literature for women.
 * Eseria's aunt, the queen, is barren; so the king has four concubines to produce heirs. Therefore Eseria and the prince are not blood related.
 * Eseria is speaking another language as if it's her first one; so when she hears words similar to Japanese in odd moments, she can't help but laugh.