Teikoku-ichi no Akujo ni Dekiai ga Tomarimasen!

There's a price to be paid for a seemingly perfect life. For Raven, the dashing young son of a duke tasked with guarding the empire, marriage represents nothing but a downward spiral into misery. Cherishing his freedom as a bachelor, Raven is perplexed when the daughter of rival House Sharen makes him a daring proposal of marriage. But there's a hitch: Lady Estrella Sharen is an infamous villainess who is feared across the empire! Raven suspects there is more to her than meets the eye, but nonetheless agrees to enter into a marriage contract...

(Source: Webtoon Entertainment)