The plot is about the unexpected romance that blossoms between a yakuza member and someone unexpected. It's appealing because of the unique mix of action and romance.
It could be someone completely new, a character created just for this fanfic. Maybe he's a normal villager who has a kind heart and fell in love with Sakura when he saw her helping people in the village. He doesn't have any ninja powers but he has a great sense of humor and that's what attracted Sakura to him.
The Yakuza games story portrays Yakuza culture in several ways. It shows their hierarchical structure. The higher - ups have great power and respect, and the lower - level members have to follow strict rules. Also, their sense of justice within their own world is depicted. They have their own way of dealing with disputes and traitors which is part of their unique culture.