The ornamental design for a mermaidsleepingbag, as shown and described.
FIG. 1 is a front view of a mermaid sleeping bag, the rear view thereof being the same;
FIG. 2 is a right side view thereof, the left side view being a mirror image thereof of a mermaid sleeping bag of FIG. 1;
FIG. 3 is a top view thereof of the mermaid sleeping bag of FIG. 1;
FIG. 4 is a bottom view thereof of the mermaid sleeping bag of FIG. 1; and,
FIG. 5 is a perspective view of the mermaid sleeping bag of FIG. 1.
The dash-dash broken line shown in FIG. 3 illustrates portions of the mermaid sleeping bag that form no part of the claimed design. The dot-dash lines shown in FIG. 3 illustrate a boundary of the mermaid sleeping bag and form no part of the claimed design. The broken line in all other views showing of portions of the mermaid sleeping form no part of the claimed design.