愛妾[aishou] beloved concubine
妾腹[shoufuku] illegitimate (e.g. born to a mistress)
妻妾[saishou] one's wife and mistress(es)
男妾[danshou] male paramour
妾出[shoushutsu] illegitimate (e.g. born to a mistress)

妾宅[shoutaku] house in which a mistress is kept
蓄妾[chikushou] keeping a mistress (concubine)
外妾[gaishou] foreigner's mistress
洋妾[youshou] Westerner's mistress

御腹[onaka] stomach
異腹[ifuku] child of a different mother
一人腹[hitoribara] taking for granted
横っ腹[yokoppara] side
横腹[yokobara] side

下っ腹[shitappara] abdomen
下腹[kafuku] abdomen
瀉腹[kudaribara] diarrhoea
下腹部[kafukubu] abdomen
割腹[kappuku] disembowelment