Summoned to another world as a "bonus" to a saintess, what awaited the heroine was a forced marriage with a poisonous bird emperor?! Rui Kanzaki was transported to another world with her younger twin sister. Her sister, having an aptitude for every kind of magic possible, is treated as a saintess. On the other hand, Rui is treated horribly due to having absolutely no magic ability and only having poison resistance. One day, Rui is married off to the emperor of a neighboring beastfolk nation in her sister's place. The emperor turns out to be a descendant of a poisonous bird clan, whose body brims with lethal toxins. A strategic marriage of a lonely emperor and a stand-in saintess - What will happen now that the lives of two completely different individuals have crossed paths?!
The Stand-In Saintess Strives to Become the Poisonous Emperor's Perfect Mate!