鬼門
き
も
ん
Meanings
1
northeastern unlucky direction; demon's gate
In traditional onmyōdō cosmology, the northeast direction is considered unlucky and is called the demon's gate. Figuratively, it can refer to a person or thing that brings bad luck or should be avoided.
Many people avoid the northeastern direction when building a house.
That boss is a person to be avoided for him.
2
Used for a personal weakness, a subject one is bad at, or a situation one finds difficult to handle. Often appears in phrases like 鬼門だ or 鬼門になる.
Math has always been my weak point.
Speaking in public seems to be his Achilles' heel.