Original sentence: In subcultural and fictional uses, a mundane is a person who does not belong to a particular group, according to the members of that group; the implication is that such persons, lacking imagination, are concerned solely with the mundane: the  and ordinary
Edited sentence: Relating to an esoteric subcategory of science fiction... In subcultural and fictional uses, a mundane is a person who does not belong to a particular group, according to the members of that group; the implication is that such persons, lacking imagination, are concerned solely with the mundane: the  and ordinary