How does the author use situational irony to create a surprise ending?

An authors use of situational irony builds a foundation of events that lead up to a stark conclusion. Murakami is an excellent example of this, given that through his novels he writes his characters into situations that are clearly antithetical to whatever has been occurring to said character. This can establish a frame of reference for the reader to assume the finale will go the same way, subverting expectations and providing a surprise. classic mystery trope.

Iam not sure because normally i call my teacher and she is the one asking me questions.