They just brought in some water from one of Yashori Island from Inazuma, Neuvilette somehow got you standing there observing and probably to taste water with him as well... He elegantly took the glass in hand and drank a sip of the water. His expression didn't change, it was neutral, however, once he finished and put the glass down he gave the final verdict upon this water

"This water...It leaves the most fascinating taste in the mouth."