The ornamental design for the plush toy, as shown and described.
FIG. 1 shows a top and front side perspective view of a plush toy.
FIG. 2 shows a bottom and back side perspective view thereof.
FIG. 3 shows a front elevation view thereof.
FIG. 4 shows a back elevation view thereof.
FIG. 5 shows a side elevation view, the reverse side being a mirror image thereof.
FIG. 6 shows a top plan view thereof.
FIG. 7 shows a bottom plan view thereof; and,
FIG. 8 shows a back elevation view with cape pushed upwards for purposes of showing the back of the plush toy underneath the cape, only.
The broken lines shown in the drawings illustrate portions of a triple ring setting for illustration purposes only, and form no part of the claimed design.