Maybe her sister had an accident or passed away unexpectedly, and it was a huge shock for the girl swimmer.
We mourn fictional characters because we form emotional connections with them. Their stories and personalities touch us, and when they face hardships or pass away, it evokes real emotions.
It's common. Sometimes we get so attached to fictional characters that their stories and fates matter to us a lot. It shows we have a rich imagination and the ability to empathize deeply.
I'm not sure as the description is very limited. It could be either. There are unfortunately real cases of such heinous acts in the world, but it could also be a fictional plot in some disturbing story.
It could be because of a misunderstanding. Perhaps there was a miscommunication or an incident where the sister was wrongly blamed for something, and Bella held onto that grudge. Say the sister accidentally broke Bella's favorite item but Bella thought it was done on purpose, which then festered into hatred in the fanfiction world.
Maybe he lost someone dear or something really important to him. That could be why he was mourning.
Well, in some novels, the saving incident might be used as a way to introduce the swimmer's backstory. Maybe he had given up swimming due to some dark event in his past, but saving the girl makes him realize he still has value and strength. As for the girl, she might see him as a hero, and this perception starts to evolve into love as she gets to know the real person behind the heroic act. They could then go through a series of events together, like going to swimming competitions as spectators, which further deepens their relationship.
The recommended novel about a girl who transformed to save her sister was " The Black-bellied Prince and the Tyrannical Princess Consort." This novel told the story of the female protagonist receiving treatment from the prince in order to save her sister. In the end, she successfully cured her sister and won the prince's love.
The following are a few novels recommended by girls to avenge their sister: [The Rebirth of a Concubine: The Return of the Poisonous Concubine]: The female protagonist was reborn, and she dug a pit to abuse the scumbag man and the eldest sister, just for revenge. 2. " Rebirth Against the Heavens: A Strategy for Revenge of Abandoned Concubine ": The female protagonist was beaten to death because of her sister's framing. After rebirth, she embarked on the road of revenge. 3. << A Guide to the Revenge of the First Daughter >>: The female protagonist lost her country overnight, her loved one abandoned her, and the fetus in her womb died tragically under her sister's knife. After her rebirth, she cleared up her past grudges, killed the scumbag emperor with her own hands, tore apart the vicious sister she raised, and her smile was filled with venom. These novels were all about girls taking revenge for their sister. The plot was thrilling and suitable for readers who liked revenge.
One common plot could be that the former swimmer, perhaps haunted by past failures or traumas in the swimming world, sees the girl in danger in a water - related situation, like drowning in a pool or a lake. His instinct kicks in, and he saves her. This event then becomes the starting point of their romantic journey as they get to know each other during her recovery and realize they have a special connection.
This is a rather unusual and potentially inappropriate situation. It could be related to some kind of abnormal psychological or emotional factors within the girl.