No, it is not appropriate. Writing such fanfiction involving sexual content about fictional characters is disrespectful to the original work and its intended audience. Fanfiction should focus on positive aspects such as character development, new adventures, or alternative storylines within the boundaries of good taste.
Writing fanfiction about sexual content involving characters is generally not appropriate. These characters are often from family - friendly franchises like Dragon Ball. Such content goes against the spirit of the original work which is mainly focused on action, adventure, and positive values. It can also make many fans uncomfortable, especially younger ones who are fans of the series.
Well, such sex fanfiction is not common and can deviate from the intended themes and characters of the original series. It's better to enjoy fan creations that enhance and expand the story in a meaningful way.
It's not suitable at all. While fanfiction allows for creative interpretations of characters, sexualizing them in this way is disrespectful to the original work. There are so many other aspects of their relationship, like their mutual respect and how they support each other in battles and in raising their family, that can be explored in a more appropriate fanfiction.
Yamcha could potentially betray Bulma. Even though they have a history together, in a fanfic scenario, he could be jealous of Bulma's growing closeness with Vegeta or her scientific achievements. So, he might do something to undermine her, like spreading false rumors about her work.
In such fanfics, Bulma might be portrayed as more adventurous in her love life. She could be shown as being open to new relationships outside of her usual circle, which might bring out different aspects of her personality, like her boldness or her ability to adapt to new situations.
Such stories are not acceptable as they can have a negative impact on the mental and psychological health of readers, especially the younger generation. We should promote positive and healthy cultural products.