Shikabane to Hanayome

They were the only two brothers in this large house. The wedding of the younger brother, now head of the family after a gruesome battle of succession, was held in a solemn manner. The bride's face is hidden behind a thick veil, and everyone calls her the "faceless wife". Then on the wedding night, as they make love, the groom lifts her veil to reveal the face of his elder brother, who was supposed to be dead.

(Source: Libre, translated and edited)

Note: Includes one extra chapter.