Dean mimicking ChaosToadette/Dreadianz' original species, Muscarian, to blend to observe (and hunt) other muskies. He is doing a decent job for turning into one of them for the first time. The mushrooms on his head are based on Cordyceps, parasitic mushrooms. He can easily change the mushroom on his head with ANY mushroom, what he chooses is more for aesthetic purposes more than anything.
Dean goes by he/they pronouns and in general doesn't care much about gender, but that is common for his species to not care about gender.
You can find ChaosToadette's work on twitter https://twitter.com/ChaosToadette