A Chappie is a person who over explains, generally with useless information that relates almost nothing to the actual sentence or story being told. Chappies can also be called out for wasting time, and the phrase comes from how they make a sentence into a chapter, giving them the Chappie nickname.

A majority of Chappies don't realize they drag on a sentence to a crawl, mainly because they suffer from some sort of mental disorder, though just because someone is a Chappie doesn't mean they particularly have a mental disorder.

when you're hungover as shit after a spending a night drunk as a skunk

A childish and immature way of saying "chapter". Mainly used in the context of fanfiction.

A pair of assless chaps, usually bought by a woman with numbi-notes.

British
.game where a person knocks on a door and runs away

Meaning a chapter in a fanfiction