1
general::
Also, bore to tears or bore stiff or bore the pants off. Weary someone through extremely dull talk or uninteresting action. For example, Sam was bored stiff by the opera but didn't dare to admit it, or Carol bores the pants off me with her constant talk of remodeling, or His books bore me to death. All four expressions convey the idea of such exasperation that one dies, weeps, stiffens with annoyance, or has one's trousers removed. The verb bore has been used in this sense only since about 1750, and its etymology is unknown. The amplifications were added between about 1850 and 1950. Also see under PANTS OFF; TALK ONE'S ARM OFF.
American Heritage Idioms
2
general::
Phrase(s): bore someone to death
Go to bore someone stiff and bore someone to death; bore someone to tears
McGrawhill's American Idioms And Phrasal Verbs