thorn in the flesh

become one flesh

To join together in marriage; to develop a unifying bond as a result of marrying.

exchange flesh

To engage in sexual intercourse.

flesh one's maiden sword

To experience or succeed in combat or struggle for the first time, as in the military or in politics.

flesh out

To complete; to create details from a basic outline, structure, or skeleton.

neither fish, flesh, nor good red herring

Synonym of neither fish nor fowl (“not easily categorized; not rightly belonging or fitting well in a given group or situation; also, not having the advantages of the various options”).

one flesh

Two people united by marriage.

pound of flesh

Something which is owed and which will be hurtful or difficult to provide; a debt owed to someone who is merciless and demanding.

press the flesh

To shake hands and socialize, especially in a political gathering.