Gosai de, Ryuu no Outei Denka no Hanayome ni Narimashita @Comic

Overview

Lonely young princess Leticia, a reincarnated princess, is married off to Diana, a kingdom blessed by dragons, as a way to get rid of her burden. Her husband is Prince Ferris, the brother of King Ferris, who is rumored to be cold and ruthless, but the two outcasts quickly hit it off! They form a secret alliance, sharing their struggles in life, enjoying rosewater afternoon tea together, bringing him late-night snacks because she worries about his small appetite, and finding solace in dreams of dragons resembling him... and unexpectedly, a fluffy and heartwarming everyday life begins!? However, the succession to the throne and the fate of Ferris, a descendant of the Dragon King, intertwined in the background of this marriage will soon lead them into the midst of a conflict. "I will definitely protect you," "I must protect His Highness." (Source: Corona EX, translated)

Source: AniList