The Grand Duke of the North's Crazy Son-in-Law

Galahad, an elite wizard and top agent of the Intelligence Bureau, was sold off as the Grand Duke of the North's son-in-law for political reasons. Meanwhile, the ice-cold daughter of the duke is the "key" to defeating the Demon King and saving the world. Determined to win her heart, Galahad approached her with his usual madness and an utterly ridiculous level of determination. However, his target is a swordmaster who burns mana, and even the slightest touch causes him to endure excruciating pain that courses through his entire body... "I want to touch her again. This time, just for a bit longer—" (Source: Naver, translated)