Akuu no Seijo: Imouto ni Nureginu wo Kiserareta Saikyou Majutsushi wa, Shoutai wo Kakushite Yarinaosu

A young girl named Soalis was a genius at magic. By the time she was ten years old, she had become one of the top court magicians in the country. Now at the age of sixteen, she is respected and called a saint by the people. Whether it be demons, Demon Kings, and Evil Gods, she has defeated anything that threatens her country. But one day, she is tricked by her own little sister, who is also a court magician. She is framed for a crime she did not commit, as she is found to have the banned magic potion, Elixir, in her room. She was tricked by her sister, whom she trusted, and without realizing the trap, Soalis was sealed inside the strongest mythical grade magic tool. However, it only took her 20 years to break the powerful seal that was supposed to last for hundreds of years. In addition, while she was sealed, she had created spatial magic to escape and return to the kingdom. While in the seal, Soalis had not aged and was still a 16-year-old-girl. In the past twenty years, the kingdom had been invaded by demons and had fallen into a critical situation. Expecting to be treated as a criminal, Soalis hid her own identity as a saint and started over. The next thing people knew, the saint had returned. She would return the favor to those who wronged her. The story of the world's restoration by the strongest saint begins here. (Source: Shousetsuka ni Narou, translated)