"Akita" to Kaite Isekai Ni Iketakedo, Hametsu Shita Akuyaku Reijo No Daiyakudeshita (Tsugikuru Books) [Light Novel]

[Machine Translation] Everyone wants to try "how to go to another world" at least once. If all you have to do is write "I'm bored" on a piece of paper and go to sleep, it's an easy way to pass the time. Midori Kima was not bored with her life, but she wanted something to distract her from her mundane life, so she tried out a small urban legend and went to sleep. Then, when she woke up, she found herself in another world! In front of her eyes was a handsome... A self-proclaimed elder brother! Apparently, Midori Kima was chosen as the understudy for the villainous daughter who "hanged herself after her fiance, the crown prince, had a change of heart and broke off their engagement to a commoner girl. Midori Kima, who was selected to play the role of the villainous duchess, "the dauphin who changed his mind and hanged himself after his fiancee changed her mind and broke off their engagement to a commoner girl," has been chosen to replace the duchess who voluntarily withdrew from the stage.

誰だって、一度は試してみたい『異世界へ行く方法』。それが、ただ紙に『飽きた』と書いて眠るだけなら、お手軽&暇つぶしには丁度いい。人生に飽きたわけではないけれど、平凡な生活に何か気晴らしをと、木間みどりはささやかな都市伝説を試して眠った。そうして、目覚めたら本当に異世界!目の前には顔の良い...自称お兄さま!どうやら木間みどりは、『婚約者である王太子が平民の少女に心変わりして婚約破棄された末、首を吊った』悪役令嬢の代役として抜擢されたらしい。舞台から自主撤退された御令嬢の代わりに、「連中に復讐を」と願うお兄さまの顔の良さにつられて、ホイホイと木間みどりは公爵令嬢ライラ・ヘルツィーカとして物語の舞台に上がるのだった。