Sylla creeps around on Thursday despite not taking the class, but is her sweetest most polite self because she is going to smell that potion come hell or high water - self-discovery for the win!
In the test batch, she smells ginger and cinnamon and other baking spices, ambergris in her mother's perfume, oxidized iron and old metal (or blood? She isn't sure, but she conveniently leaves that detail out), scotch, and cigarette smoke. The conclusion she draws and keeps to herself is that it smells like Mummy and Daddy, and she's not too bothered when she thanks Elmasry kindly for his time and waltzes back on out.
And just for fun because PFFT who would even, associated with Sylla: freshly-laundered linen, wool, perfume that smells almost tart like pomegranate juice.