The ornamental design for a pencap, as shown and described.
FIG. 1 is a bottom front right perspective view of a pen cap showing my new design;
FIG. 2 is a top front right perspective view thereof;
FIG. 3 is a right rear top perspective view thereof;
FIG. 4 is a front elevation view thereof;
FIG. 5 is a right side view thereof, the left side view being a mirror image thereof;
FIG. 6 is a top plan view thereof;
FIG. 7 is a bottom plan view thereof; and,
FIG. 8 is a bottom front right perspective view of the pen cap of FIG. 1 shown attached to a pen.
Portions shown in even-length broken lines are environment. Broken lines of uneven length illustrate the boundary of the claimed design. The broken lines form no part of the claim.