As parrotfish grow, they go through two phases, initial and terminal. Initial phase parrotfish can be male or female, but in some species are always female. I ran a photo of an initial phase ember parrotfish here.
This ember parrotfish is in its terminal phase and is what is known as a supermale. Terminal phase parrotfish are always male and, as John Hoover notes, ‘supermales are almost always reversed-sex females.’ Supermales also tend to brightly colored, like this one.
The smaller, following fish is a Christmas wrasse. Parrotfish are often trailed by one or other of the wrasses, looking to latch onto things to eat, dislodged by the larger fish grazing for algae on the coral.
In my attempts to identify what I see in the water, I use John P. Hoover’s book The Ultimate Guide to Hawaiian Reef Fishes, Sea Turtles, Dolphins, Whales, and Seals. His website is hawaiisfishes.com.