As Du Lang handed the items to Shen Yanxiao, he secretly 'sized up' that 'little customer.' He had been around the Black City for years, and based on the kid's facial bone structure, he could discern that Shen Yanxiao's appearance was not her own.
Disguise masks were one of the most common items in Black City, but it was also apparent that the quality of the mask that Shen Yanxiao had was more exquisite than the highest quality ones sold in the Black City. If Du Lang did not have an exceptional understanding of the human bone structure, he would not have noticed her disguise mask.
He knew that no simple situation would need items from a fifth-ranked magical beast. Those items were usually only required in advanced potions and magical arrays. Even though the little kid looked inconspicuous, he was also quite generous with his money and behaved in a manner that was not consistent with how he looked.
