One Piece – Thundergod Marine - Chapter 66 Limit Part 1

The protagonist, Winnie (文尼), confesses his love to his childhood friend—the princess he’s been secretly in love with for years—but is brutally rejected in public. His heart shatters, he’s humiliated and ridiculed, and he collapses unconscious. When he wakes up, he vaguely remembers his past life’s memories and realizes he has transmigrated into the world of an otome game he played before. At first, he’s thrilled, thinking, “Nice! I must have been reincarnated as a villainous side character who disrupts the protagonist’s romance, right?” But then… surprise! He’s not just the villain—he’s the “Saintess”!

A Count’s Daughter who lost in the running to become the Second Prince’s fianceé, Camilla. The Prince chose a Baron’s daughter as his fianceé, and the world blessed the two’s love as fated. On the other hand, Camilla who was tailored and elevated as the love’s villain in the end, as punishment she was made to marry a terribly fat and ugly man――called『Toad of the Swamp』from his appearance, a lord of a remote region named Alois.

Emperor Gabela: Imperial legions are unstoppable on land.

Great Orc Chief: All the warriors of the tribe can count as ten.

Jade Realm Elf King: The forest ranger has never missed a shot.

Chairman of the Horn Bay Alliance: The alliance fleet is the undisputed ruler of the sea.

A mysterious organization: The prophesied era will finally come.

Paul Grayman: I am not targeting anyone. Everyone here is rubbish.

Start the journey of guns and cannons crushing the low-magic plane…

(This is an old-fashioned story about climbing a technological tree in another world to farm for hegemony. The author has limited knowledge and may make some mistakes in technical details. Criticism and corrections are welcome)

- Description from novelbuddy

After 2000 years has passed, the ruthless demon lord has just been reincarnated! But his aptitude at an academy for nurturing candidates for demon lords is, “Inept”!?