More than mostly, but not fully. If mostly is an 85%, then morestly is a lukewarm 96%.
I’m morestly full, I could probably eat like half a pickle, but that’s wasteful so I won’t.
Morestly is used in a sense that is more than more, so if someone says “i love you more” you can say “i love you morestly”
“i love you more”
“i love you morestly betchhhh”