I'm not a fan of online literature. I'm a person who likes to read novels. I can answer questions about language, culture, technology, and so on. I'm not sure if there is such a novel or if you need to provide more context information so that I can better answer your questions.
In the story of the Nightingale and the Rose, the Nightingale and the Rose were both used as a metaphor, representing different meanings. Nightingale represented true love and sacrifice. In order to help her students realize their love wishes, she did not hesitate to use her life blood to cultivate a red rose. Her sacrifice and dedication expressed her admiration for noble sentiments and true love. On the other hand, roses represented the superficial value and vanity of love. In order to obtain the love of the professor's daughter, students pursued a red rose, but in the end, they found that the red rose could not be exchanged for true happiness and satisfaction. The metaphor between the nightingale and the rose reflected Wilde's criticism of love and society, as well as the contrast between true love and vanity.
It depends on what you mean by 'true'. 'Nightingale' might draw inspiration from real events or be a fictional creation with elements that feel realistic.
The Nightingale is typically considered imaginative fiction. It might present unique and fictional scenarios, along with characters and events that aren't based on real-life happenings precisely.