adulterer and adulteress; adulterous couple
A formal or literary term for a man and woman involved in an adulterous relationship. Not used in everyday conversation; more likely to appear in legal or historical contexts.
In that novel, a scene is depicted where the adulterous couple meets secretly.
Compound of 姦夫 (adulterer) and 姦婦 (adulteress), each using the character 姦 meaning 'wicked' or 'adultery'. The reading is on'yomi.