expression, noun
furious facial expression; face like a demon
Describes a terrifyingly angry face, often used when someone is enraged or glaring fiercely.
彼は鬼の形相で怒鳴り込んできた。
He came in yelling with a furious look on his face.
鬼の形相で睨まれて、思わず後ずさりした。
He glared at me with a demonic expression, and I instinctively stepped back.
A general term for an angry face; 鬼の形相 is much stronger and more vivid, implying a terrifying, demon-like rage.
Literally 'the face of an oni (demon)'. The phrase uses the image of a fearsome Japanese demon to describe an extremely angry facial expression.