Banished Duke's Daughter Wilhelmina Finds Happiness With the Strongest Commoner

Tsuihou Sareta Koushaku Reijou, Wilhemina ga Shiawase ni Naru Made.: Saikyou no Heimin, Sekai ni Kakumei wo Okosu
追放された公爵令嬢、ヴィルヘルミーナが幸せになるまで。 ~最強の平民、世界に革命を起こす~

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Tsuihou Sareta Koushaku Reijou, Wilhemina ga Shiawase ni Naru Made.
追放された公爵令嬢、ヴィルヘルミーナが幸せになるまで。
novel

Wilhelmina was raised to be queen. The Crown Prince, who dislikes her, schemingly demotes her to commoner status, but she is not about to take it lightly. She supports her husband Alexi's research, backing him up with all her might. She even starts a company with the invention of the century, the magic element crystallization device, which will shake up the nation and the world. What is her "revenge" plan that will devotedly support her husband and transform him from a humble researcher into a top-notch businessman? (Source: Earth Star Entertainment, translated) *Note: Includes three extra chapters.*