Sasuke often appears in different story arcs of the Boruto manga, depending on the current plot and mission. Sometimes he's on a solo mission, sometimes he's involved in events related to the village.
Naruto is likely to be popular too. Even though it's a Boruto x Sasuke fanfic, Naruto's relationship with both of them is so important. He could play a role in supporting them from the sidelines or even getting involved in a crucial part of the story.
There were a few novels that could be recommended. One of them was " Nirvana Rebirth: The AdorkablePrincess Wants Candies." The protagonist wanted to eat candy the first time they met, and the plot was very sweet. The other book was " You're Not as Bright as I Am ". The first time the male and female leads met was during an internship. The female lead grabbed the male lead's wrist and refused to let go. The male lead refused the female lead's invitation, but in the end, he sent the female lead home. The other book was " The Conquest Game: A Beautiful Wife Is Hard to Tame." The male and female protagonists met for the first time in a bar, and the male protagonist mistakenly thought that the female protagonist was a lady. The second time they met was on the racing track. These novels all have different plots and backgrounds. I hope you can choose a novel that you like according to your preferences.