How is “finish up” used?

In Unbreakable (2000), one line is: “Why don't you go upstairs now and let me finish up, okay?”

Which movie is “finish up” from?

The clip at the top of this page is from Unbreakable (2000).

to complete the remaining part of a task, meal, shift, or piece of work

British · Heard in 23 movies

Editorial100% of films
to complete the remaining part of a task, meal, shift, or piece of work

Definitions from the Oxford Advanced Learner's Dictionary, 9th edition

Why don't you go upstairs now and let me finish up, okay?

Said in 8 films · #1