Shinyuu Ouji to Koshiginchaku: Oshi no Ouji ni Kyuukon Sarete Komattemasu

I was cursed to become a woman in place of the prince, and then he proposed to me!? My best friend from childhood, the high-spec Prince Vincent, and me, his follower Renoa. Though I've always been a loyal yes-man... Even if you're taking responsibility for me, I can't accept that proposal! The infatuating love story between a troublesome prince and his scapegoat attendant!

(Source: Flex Comix, translated)