poetic justice vs aftermath

poetic justice and aftermath both are nouns.

Word	Noun	Adjective	Verb	Adverb
poetic justice	Yes	No	No	No
aftermath	Yes	No	No	No

As nouns, aftermath is a hypernym of poetic justice; that is, aftermath is a word with a broader meaning than poetic justice:

Other hypernyms of poetic justice include consequence.

poetic justice (noun)	aftermath (noun)
an outcome (good or bad) that is well deserved and fitting	the outcome of an event especially as relative to an individual
	the consequences of an event (especially a catastrophic event)