I'm Giving the Disgraced Noble Lady I Rescued a Crash Course in Naughtiness

Allen, the misanthropic wizard who lives deep in the woods, is known as the "Devil King" and is feared by the people around him. He leads a solitary life away from humans, until one day he comes across a young girl named Charlotte who has fainted in the forest. Charlotte, despite her innocence, has been accused of committing wicked deeds and has had her engagement cancelled, forcing her to flee her country. Upon learning this, Allen remembers the pain of betrayal he once experienced from a group he had considered his comrades. After hearing the pitiful story of the 17-year-old girl, Allen decides, "I will allow her to live in my mansion and teach her all kinds of naughty things..." (Note: The mentioned title and synopsis are fictional and not based on an actual TV series.)