Abstract: A flushing device for disposing of human waste includes a bowl. A trap section, disposed in a draining path extending from the bowl, has a rear end that pivots between upper and lower positions. A case main body communicates with an external drain pipe and houses the trap section. A driving mechanism moves the trap section between the upper and lower positions. A water supply mechanism supplies water to the bowl. A ring is fitted on the rear end of the trap section. The ring has notches on upper and lower sides such that side edges of the ring have an arcuate shape. The case main body has an arcuate shaped profile that is substantially identical to the arcuate shape of the ring, wherein as the trap section pivots from the upper to lower position, a gap between the arcuate shape of the ring and the upper portion of the rear face inside the case main body is wider than the gap between the arcuate shape of the ring and the lower portion of the rear face inside the case main body.