"A fighting game is a type of video game where the player controls an on-screen character and engages in close combat with an opponent. These characters tend to be of equal power and fight matches consisting of several rounds, which take place in an arena.
" - Wikipedia
Most fighting games are built around mostly fantasy storylines
which unravel as one progresses through the game. Usually there is a simple plot or premise which takes the gamer into the world surrounding the fighting game. Once the gamer picks a fighter, he then goes in detail into the storyline of the chosen fighter and how they are associated with the general game story/premise unlocking a new part of the story as they progress.