Milk Frother

FIG. 1 is a top-left perspective view illustrating the design for a milk frother. FIG. 2 is a front view thereof. FIG. 3 is a rear view thereof. FIG. 4 is a left-side view thereof. FIG. 5 is a right-side view thereof. FIG. 6 is a top view thereof; and, FIG. 7 is a bottom view thereof. The broken lines in FIGS. 1 - 7 show portions of the article that form no part of the claimed design.