I think "一触即発" can be used to refer to the personality of a person and means "quick to anger or get emotionally upset". If it cannot, please just say "no it cannot" and no reason to read further.
This is how I think it can be used:
talking directly to the person:
「さすが一触即発の性格でしょうね。えと、なのに、ふつつかな私を許してください。申し訳ありません。」 (You have such a personality that is quick to anger. Um, anyway, please make allowances for my incompetence. I have no excuse.)
talking with someone about a third person who is not present (Tanaka-san):
「田中さんは一触即発の人だと思わない。」(Do you think that Tanaka-san is quick to anger?)
- Does it make sense to even refer to a personality as 一触即発? Does it sound funny, make a native speaker laugh? Or, a personality cannot be defined that way?
- Should it be "一触即発の人" or "一触即発の性格がある人"?
- Either way, it is very informal / humorous way among friends to describe someone who easily gets upset?
- 人柄 instead of 性格?