For a change the second one isn’t “off”.
I was speaking to my colleague in Tokyo last week and realised that while “[Good] morning” was accurate for me it wasn’t for him. Likewise, “[Good] afternoon” wasn’t the correct salutation either. Therefore I started off with “Morternoon” which he grokked immediately. He didn’t respond with “Aftering” though which I found mildly disappointing.
A quick search would suggest I’m not the first to think of this so I can’t quite claim this as my own neologism.