As a fan of online literature, I can't recommend any BS-novels because BS-novels usually refer to novels that lack nutritional value, vulgar content, violence, and eroticism. These novels may mislead readers and harm their physical and mental health. I strongly recommend that you do not read these novels and instead read some healthy and educational books.
One idea could be a story where a new character, the OC, is a young chef who idolizes Katakuri. They enter a cooking competition in the Big Mom Pirates' territory and Katakuri takes notice. The OC tries to prove themselves worthy of his respect through their cooking skills.
One popular type of OC is a female pirate who is as strong - willed as Katakuri. She challenges him in a battle of wits and strength, and their interactions create a lot of tension and intrigue in the fanfiction. For example, she might try to steal a precious treasure that Katakuri is guarding.
One great Katakuri x OC fanfiction is 'A Sweet Encounter'. In this story, the OC is a baker who stumbles into Katakuri's world. The author does an amazing job of building their relationship gradually. It shows how the OC's kind nature starts to break through Katakuri's tough exterior. Another interesting one is 'The Unlikely Bond'. Here, the OC has a special power that intrigues Katakuri, and they form a bond while facing common enemies.
A person who tells bs stories often lacks honesty and integrity. They could have various motives like covering up their own mistakes or trying to make themselves look better than they are. This behavior can lead to broken relationships and a loss of credibility.
The popularity of Katakuri x OC fanfiction lies in the fact that Katakuri is a complex and interesting character. His stoic nature and his powers make him an appealing figure. When paired with an original character, it allows for a lot of creative freedom. Writers can create unique backstories for the OC that interact in interesting ways with Katakuri's own story.
Rebecca could potentially be in Luffy's harem. After Luffy helped her in Dressrosa, she might develop feelings for him. She is a strong - willed and kind - hearted character. Another could be Shirahoshi. Luffy has a special connection with her as he saved her from being captured. Her gentle and innocent nature would contrast with some of the other more assertive members of the harem.
Their relationship could develop through mutual respect. Luffy respects Whitebeard as a powerful and respected pirate, and Whitebeard respects Luffy's determination and potential. For example, they could start with a simple exchange of stories about their adventures at sea.