The ornamental design for a mermaidsleepingbag, as shown and described.
FIG. 1 is a perspective view of a first embodiment of a mermaid sleeping bag showing my new design;
FIG. 2 is a front view thereof;
FIG. 3 is a back view thereof;
FIG. 4 is a side view thereof;
FIG. 5 is a top plain view thereof;
FIG. 6 is a bottom plain view thereof;
FIG. 7 is a perspective view of second embodiment of a mermaid sleeping bag showing my new design;
FIG. 8 is a front view thereof;
FIG. 9 is a back view thereof;
FIG. 10 is a side view thereof;
FIG. 11 is a top plain view thereof; and,
FIG. 12 is a bottom plain view thereof.
The evenly spaced broken lines illustrate stitching on the mermaid sleeping bag and form part of the claimed design. The other, unevenly spaced lines are contour lines that form part of the claimed design. The cross hatch surface shading indicates fabric and is understood to exist throughout all surfaces of the claimed design.