expression, i-adjective
unable to read the room; unable to pick up on the mood; socially oblivious
Describes someone who fails to sense the atmosphere or unspoken social cues in a situation. Often used critically or jokingly; the abbreviation KY (ケーワイ) is common in casual online contexts.
See also: 空気を読む
彼は空気が読めないから、いつも場をしらけさせる。
He can't read the room, so he always kills the mood.
That person keeps making socially oblivious remarks.