Mundane detail is the lifeblood of an absurd, fantastical story. When absurdism or magical realism works, we experience the magic/absurdity as out of the ordinary but plausible. This happens because the framework of reality used is well described.
Mundane detail is one great way of describing a framework of reality. People who have read Murakami’s works find realism juxtaposed against fantasy. He isn’t the first writer to do so, but his attention to chores and mundane activities grounds the plot allowing the fantasy to flourish.
Reality in fiction is fake. All fiction is essentially fantasy as it arises from the writer’s mind and cannot be an objective representation of a situation even in the best of cases. Realism and reality then become a tool to be used instead of being the end all be all goal of fiction. This raises another question: what is reality in fiction?
Reality in fiction can be considered as the level of sensual detail that is consistent with how the average human being perceives the world.
In another sense, we can say that the level of detail congruent with the everyday experiences or expectations of the reader is reality in fiction. So increasing the level of detail is itself a fantasy and could be called hyperrealism.
Consider a character casually glancing at a wall: noticing that a room’s wall is blue is real, but if the colour of the wall changes by the second it is fantastical, and if the character can see a crack in the upper right corner of the wall that is barely visible at a glance then it is hyperrealism where the detail is factual, but the observation of it is not consistent with the reader’s experience. Fantasy worlds can be made real, or the real world made fantastical by leveraging detail and the sensory perception of detail.