My Fair Bad Lady (マイ・フェア・バッドレディ) is a side story featured in Gekkan Comic Alive. It was later adapted in Re:Zero Tanpenshuu Volume 3.
Subaru is informed that tomorrow the mansion will host the famous chef Dias Lepunzo Elemanso Oplane Fatsbalm VI. When informed of it with rumors, Subaru thought that it was a plan of Roswaal to qualify the table manners of Emilia. When the chef arrived, he prepared the food while Subaru crossdress in order to help Emilia. Finally when everyone gathered, Subaru was stunned by his plate. He confessed his thoughts to the chef, only to discover that this was actually Rodriguez and that the rumors were from his teacher, the real chef. When they left the mansion, Roswaal said goodbye and alone, he happened to see Subaru crossdressing.