The word disgrace
is the Hebrew word ḥěsěḏ. The term usually means steadfast love.
Here it is used as a homonym, carrying the opposite meaning. A homonym refers to two words that have the same spelling but have different meanings. The wordplay demonstrates a move from good, brotherly love to one that is perverse and degenerate.
17 “If a man takes his sister, a daughter of his father or a daughter of his mother, and sees her nakedness, and she sees his nakedness, it is a disgrace, and they shall be cut off in the sight of the children of their people. He has uncovered his sister’s nakedness, and he shall bear his iniquity.