We report the case of a 58-year-old male with prior Billroth II gastrectomy who presented with worsening abdominal pain. Contrast-enhanced CT revealed a hyperdense, corticated, triangular-shaped foreign body (FB), consistent with a chicken bone, which had undergone retrograde migration and become impacted in the afferent duodenal loop. The FB's orientation and location were precisely characterized, with associated inflammatory changes but no perforation. Push enteroscopy confirmed and successfully removed the FB. Post-procedural imaging excluded complications. This case highlights the diagnostic value of CT in identifying ingested FBs and illustrates the exceptional risk of retrograde FB migration and potential perforation in the afferent loop following Billroth II surgery.