The ornamental design for a butterflynovelty, as shown and described.
FIG. 1. Is a left side elevational view of my butterfly novelty with the right side elevational view being a mirror image thereof and with the dotted lines showing being for illustrative purposes only and to which no claim is made;
FIG. 2. Is a front elevational view thereof with the dotted lines showing being for illustrative purposes only and to which no claim is made;
FIG. 3. Is a rear view elevational thereof with the dotted lines showing being for illustrative purposes only and to which no claim is made;
FIG. 4. Is a top plan view therof; and,
FIG. 5. Is a bottom plan view thereof with the dotted lines showing being for illustrative purposes only and to which no claim is made.