shoes, boots
沓 centers on footwear that covers the foot: shoes or boots. The idea is something worn on the feet for protection or walking.
沓 combines 水 (water) and 日 (sun), but the historical origin is uncertain. It may have originally depicted something related to stepping or covering, but the modern form does not clearly reflect that.
Imagine water 水 splashing over the sun 日, and you need shoes to keep your feet dry and protected. 沓 are the shoes or boots you wear.
For トウ, picture putting on tall boots that reach your toe: toe -> トウ, and the boots cover your feet.
footwear carrier; servant who carried his master's footwear
lesser cuckoo (Cuculus poliocephalus)
footwear carrier; servant who carried his master's footwear
shallow clogs (worn by nobles; originally made of leather, later made of black lacquered paulownia)
horseshoe
black-lacquered cowhide boots with curved toes, metal buckles, and brocade tops (worn with ceremonial dress)