Perhaps because fictional stories can offer different interpretations of death, which is related to Thanatos. They can show death as a peaceful transition or a tragic event, etc.
One common theme is sacrifice. In many such stories, one or both of the lovers sacrifice something major, often related to their own life or well - being, for the sake of the love. For example, in some vampire - human love stories, the human might sacrifice their normal life to be with the vampire.
One example could be the story in 'Romeo and Juliet'. Their love was doomed from the start, much like a Thanatos - or death - influenced love. Romeo and Juliet's families' feud led to their tragic end, with death being a central part of their love story.
Thanatos is often associated with death in Greek mythology. Maybe it could imply that the concept of death (represented by Thanatos) has an affinity for fictional stories perhaps because they can explore themes of mortality, the afterlife, and the human condition in unique ways.
There isn't really a classic 'Thanatos and Death love story' in the most common understanding of Greek mythology. But if we were to create one, it could be that Thanatos, who is often depicted as a rather solitary figure in his task of taking lives, meets Death in a more personified form. They might start to understand each other on a deeper level as they both deal with the same fundamental aspect of existence. Their love could grow out of a mutual respect for their roles, and they would become a sort of power couple in the realm of the afterlife, with Thanatos handling the physical act of taking souls and Death being more of the overarching concept that he serves.
Another possible theme could be the acceptance of fate. If the story involves Thanatos, the characters may have to come to terms with their own mortality or the mortality of their loved ones. And love could be the driving force that helps them in this acceptance, guiding them through the difficult journey of understanding and living with their fates.
One possible plotline could be that Thanatos, who is often seen as a cold and efficient agent of death, starts to question his role when he meets Death in a more personal way. He begins to feel emotions he's never experienced before and they fall in love. Another could be that they are both lonely in their existence as figures associated with the end of life and find solace in each other. They might then face challenges from other underworld entities who are not happy with their new - found relationship.
There's 'A Walk to Remember'. It's a story about love that overcomes obstacles and has a deep emotional connection, similar to what one might expect from 'Thanatos Love Story'. It's a story that tugs at the heartstrings and shows the power of love in the face of difficulties.
One great Percy son of Thanatos fanfiction could be one where he teams up with other demigods to face a new and powerful threat. Maybe a story that delves into his relationship with his father Thanatos in more depth, showing how that affects his powers and his place in the demigod world.
Love stories can be both real and fictional. In real life, there are countless examples of people falling in love and having beautiful stories. But in fiction, authors use their imagination to create romantic tales that we enjoy. So, it's a mix of both!