We approached a female college student with an offer: "Would you like to try a simple part-time job helping develop a bidet toilet seat?" and asked her to participate in an anal observation session. Though initially hesitant, she agreed, and we conducted a detailed interview about her history of anal sex and her usual physical condition. After that, we examined her clean, well-maintained anus. To simulate the gentle touch of a bidet, we licked her anus thoroughly, monitoring its elasticity, size, and position. After obsessively stimulating her anus with our tongue, we moved on to cunnilingus under the pretense of checking the bidet function. As her anus and pussy were licked repeatedly, she naturally became fully aroused. Finally, the staff proceeded to vigorously fuck her with lewd, relentless thrusts.