FIG. 1 is a perspective view of a bathroom timer, as viewed from the top left side, showing my new design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is back elevation view thereof;

FIG. 4 is side elevation view thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a bottom plan view thereof;

FIG. 7 is front elevation view of a mounting sleeve for the bathroom timer thereof;

FIG. 8 is back elevation view of the mounting sleeve thereof;

FIG. 9 is a top left perspective view of the bathroom timer in the mounting sleeve thereof;

FIG. 10 is a front elevational view thereof; and,

FIG. 11 is a back elevational view thereof.

The broken lines in the drawings depict environmental subject matter that forms no part of the claimed design.