Seijo no Ane desuga, Saishoukakka wa Munou na Imouto Yori Watashi ga wo Suki na You desu yo?

Synopsis

Reina, whose life revolved around her younger sister, was finally supposed to be free from her sister's control. But the next moment, she was enveloped in light, and before her eyes was her sister, beaming and saying, "I've missed you!" It seems her sister, summoned to another world as a "saint," had summoned Reina to dump all her chores on her. Wanting to escape her life of being used as training wheels by her sister, Reina realizes that Prime Minister Edvard, who summoned her, is also having trouble dealing with her sister's selfish behavior, so she offers to help him. What started as a relationship based on mutual benefit somehow turns into a situation where, as she tries to fulfill Edvard's unreasonable demands, he begins to dote on her!? The otherworldly reform and romantic battle is finally getting a comic adaptation! (Source: AlphaPolis, translated)