on the edge of your seat = on the edge of your chair
very excited and giving your full attention to something – informal
RELATED IDIOMS :
set his teeth on edge
cause someone to feel intense discomfort or irritation
This is an expression used in the Bible to describe the unpleasant sensation caused by eating something bitter or sour : every man that eateth the sour grape, his teeth shall be set on edge (Jeremiah 31 : 30).
1997 - Kate O'Riordan - The Boy in the Moon Julia's voice sustained a quavery note that set Brian's teeth on edge.
take the edge off something
reduce the intensity or effect of something, especially something unpleasant or severe.