Bicorn: A Bicorn is an European monster with the suggestion of demonic influence. The bicorn was a fat and flesh eating monster that grew by consuming faithful or wife bullied husbands.
Chichevache: The Chichevache is the female equivalent or rival to the Bicorn. Whereas the Bicorn is fat and fed off husbands; the Chichevache is always thin and feeds off loyal and enduring wives.
In Canterbury Tales (Chaucer) the bicorn is fat as there is no shortage of bullied husbands and the chichevache thin due to the rarity of faithful wives.
The Bicorn is a mythical creature with demonic undertones. In Europe's medieval literature this fabulous beast is referenced as a plump female monster, resembling a well-fed panther with a human face and a broad grin, which grows fat through feasting on the flesh of 'hen-pecked', faithful, enduring husbands.
Wikipedia : Bicorn (also known as Burrowing Bicorn, Bicorne) is a mythological creature with two horns that has the reputation of devouring kind-hearted and devoted husbands, and is thus plump and well fed. His counterpart is the Chichevache, which devours only obedient wives and is therefore thin and starving. The Bicorn is a tremendously quick burrower, and is notorious for eluding capture. The configuration of the creature's two horns remains a mystery, as when captured, it 'drops' both horns, much as an iguana drops its tail.
JPN Wikipedia : バイコーン(Bicorn)は、伝説上の動物。二角獣(にかくじゅう) とも呼ばれる。 二本角をした馬でユニコーンの亜種といわれる。また、ユニコーンは純潔を司るのに対し、バイコーンは不純を司るとされる。 ある説では、このバイコーンこそがユニコーンの原型であるという。