doc.css("#cat10 #forum46").each do |grab|
  genre = grab.at_css(".forumtitle").text
  subgenre = grab.css(".subforum a").text.split

  puts "#{genre}"
  puts
  puts "#{subgenre}"

end

OUTPUT:

Dirty House Music

["Electro", "HouseDutch", "HouseHard", "ElectroMoombahtonFidgetAcid", "HouseDirty", "House", "Albums"]

DESIRED OUTPUT

["Electro House", "Dutch House", "Hard Electro", "Moombahton", "Fidget", "Acid House", "Dirty House Albums"]