She made three international appearances in 2009: she jumped in the triple jump qualifiers at the 2009 European Athletics Indoor Championships, was eleventh at the 2009 European Team Championships, and then represented Germany for the first time at world senior level, taking part in the heats at the 2009 World Championships in Athletics in Berlin. That year she had won at the 2009 German Athletics Championships, improved her indoor best to 14.06 m and set an outright best of 14.20 m outdoors in Ulm. Demut retained her indoor German title the year after and had her fourth straight win outdoors at the 2010 German Athletics Championships. She jumped for her country at the 2010 European Athletics Championships, but failed to record a mark in the triple jump qualifiers.