Step 10: Draw the bat's open mouth under the nose. The shape is similar to a diamond. Use quick, short strokes to represent fur.

Step 11: Draw the bat's sharp teeth inside the mouth. The teeth are pointy, triangle-like shapes. Don't draw every single tooth. Just draw a few to give the sense of the teeth.

Step 12: Draw a few quick, short strokes around the bat's mouth to represent fur.

Step 13: Use the arcs on the bat's head as guides to draw the bat's ears. Darken the arcs and make them curvier at the base. Draw some quick, short strokes at the bottom for fur. Draw a few lines within the ear to represent the inner ear structure.

Step 14: Use the original circle as a guide to draw the rest of the bat's head. Use quick, short strokes as you follow the path of the circle for a fuzzy look. Draw a few extra lines inside the head for extra detail.