What is the ruling regarding sexual intercourse with a female relative by blood (*mahram*) who was purchased, if she is one whom the purchaser is obligated to emancipate?

Primary text

The prescribed punishment (Hadd) is obligatory upon the man. We are unaware of any differing opinion on this matter. The rationale is that ownership (*milk*) is not established over her (due to the obligation of emancipation), meaning the legal misconception (*shubhah*) necessary to negate Hadd is absent.