'Relations' in the Bible

‘No one shall approach any blood relative of his to uncover nakedness (have intimate relations). I am the Lord.

You shall not uncover the nakedness of your son’s daughter or your daughter’s daughter; their nakedness you shall not uncover, for they are your own nakedness [that is, your own descendants].

You shall not uncover the nakedness of your mother’s sister, for she is your mother’s blood relative.

You shall not marry a woman in addition to her sister as a rival while she is alive, to uncover her nakedness.

‘If a man takes his sister, his father’s daughter or his mother’s daughter, so that he sees her nakedness and she sees his nakedness, it is a disgrace; and they shall be cut off in the sight of the sons of their people. He has uncovered his sister’s nakedness; he bears [responsibility for] his guilt.