The authors present simultaneous UBVRI and infrared JHKL light curves of the short-period RS CVn system ER Vul, and study both the mean level and depths of eclipses. They also point out some peculiar features, present in the light curves over time, which are frequently shown by other RS CVn short-period systems at about the same phase values, suggesting a common origin. It seems difficult, however, to reconcile the usual interpretation based on the presence of starspots with the observed time variations at the mean level and depth of the eclipses. The photometric colors indicate ultraviolet and infrared excesses, which seem to originate in hot circumstellar matter.