Well, a siren novel could be a story where the main character is either a siren or has an encounter with one. It might explore the siren's powers, like their ability to sing and lure sailors. It could also be a love story, where a human falls in love with a siren, which would bring a whole lot of complications due to their different natures.
A siren novel can be seen as a form of fictional work that takes the idea of sirens as its central or significant element. In such a novel, the author might use the siren as a symbol of danger and beauty combined. The plot could involve a quest related to sirens, like trying to break their spell over a certain area or a group of people. Or it could be about a siren's journey to understand the human world, with all the cultural clashes and emotional upheavals that would entail.
A siren novel is likely a type of novel that involves the concept of sirens. Sirens are often mythological creatures, half - woman and half - fish in many stories. So a siren novel might be a story that revolves around these alluring and mysterious beings, perhaps with themes of temptation, the sea, and adventure.