It's a boy, and if you do get a kok/hump growing it usually doesn't show up until the fish is at least 7 inches. Some grow one and some don't, genetic gamble.
Kok doesn't always = Male fish.
My Female has a bigger kok than my male who is almost 2 X's bigger.
Which leads me to believe she's more midas.
I rescued her thinking it was a male, until she started laying eggs weekly I never new.
Once large enough it's quite easy to determine the sex of a cichlid by venting it.