You are looking at the HTML representation of the XML format.
HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
To see the non HTML representation of the XML format, set format=xml.
See the complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <query-continue>
    <allfileusages gafcontinue="BanderadeEstadosUnidos.png|2627" />
  </query-continue>
  <query>
    <pages>
      <page pageid="9" ns="0" title="Uncle Kage" />
      <page pageid="927" ns="0" title="Baka Sukonku" />
      <page pageid="991" ns="0" title="Fox Amoore" />
      <page pageid="2602" ns="0" title="Fyko Fox" />
      <page pageid="2691" ns="0" title="Amadeus Chaffe" />
      <page pageid="2806" ns="0" title="Rackus" />
      <page pageid="2839" ns="0" title="Jvno&#039;s Sacrifice" />
      <page pageid="2848" ns="0" title="Kobe Wlf" />
      <page pageid="2925" ns="2" title="Usuario:Latranz Juarenz" />
      <page pageid="2962" ns="0" title="Latranz" />
    </pages>
  </query>
</api>