The ornamental design for a case for styluspen, as shown and described.
FIG. 1 is a top, front and right side perspective view of a case for stylus pen showing my new design;
FIG. 2 is a bottom, rear and left side perspective view thereof;
FIG. 3 is a front elevational view thereof;
FIG. 4 is a rear elevational view thereof;
FIG. 5 is a left side view thereof;
FIG. 6 is a right side view thereof;
FIG. 7 is a top plan view thereof;
FIG. 8 is a bottom plan view thereof; and,
FIG. 9 is a reference view showing the case for stylus pen in an exploded stated with a stylus pen to be held.
The broken lines in the drawings depict portions of the case for stylus pen which form no part of the claimed design. The oblique shade lines in the drawings represent a reflective surface.