The portside head is very large. Its divided into 3 areas. Aft is the
engine hatch, which also serves as
storage for coolers and other large items. Next is the
shower area. While it is not divided from the head by a built in 'stall', it does provide a designated area for showers, isolated from the 'business' portion of the head by a glasslike extrusion and a shower curtain that connects to the extrusion and extends to the area aft of the sink. It allows one to shower, and another to use the sink/toilet without getting wet.
I do not have a my own picture but found something on line that can demonstrate somewhat better than verbalizing. The red arrows show the areas that the shower curtain will attach. When not in use, it folds behind the glass extrusion.