The ornamental design for a bathunit, as shown and described.
FIG. 1 is an elevated top perspective view of a bath unit showing my new design, the broken lines shown being for purposes of showing the environment only, and form no part of the claimed design;
FIG. 2 is a top view thereof, the broken lines shown being for purposes of showing the environment only, and form no part of the claimed design;
FIG. 3 is a side view thereof;
FIG. 4 is an end view thereof, as seen from the left of FIG. 3;
FIG. 5 is an end view thereof, as seen from the right of FIG. 3;
FIG. 6 is a side view thereof; and,
FIG. 7 is a bottom view thereof, the broken lines shown being for purposes of showing the environment only, and form no part of the claimed design.