characterless       
adjective uk/ˈkær.ək.tə.ləs/ us/ˈker.ək.tɚ.ləs/
 无特色的;平淡无奇的;平凡的
a characterless person or thing is not interesting or has no style or unusual qualities
  It's just one of those characterless modern cities. 这不过是那些毫无特色的现代化城市之一。 
 a perfect but characterless face 一张完美但毫无特色的脸 
 Synonym: nondescript