Na, the monster girl idea has been around since the very early days of the game. DC basically spend a year trolling people on stream that there's a monster girl in the game that "nobody" had found and that people should look harder. And then he released Aqua as surprise.
Next to that there has never been really a poll on patreon about the actual content of the game (excluding the one where he asked wich monster girl people would like to see). Polls simply determin which character is going to get the next update but they don't say what kind of content should be included. I mean sure, he does a lot of polls on picarto as well but he doesn't take those very serious.
I can testify to that as a Mod on Picarto (which is no big deal as we have to many mods to begin with) you get asked alot of stuff and many ppl think you know more as patreons do. Which we do not. We know exactly the same stuff as ppl on Discord or Patreon.
If i got a € for every time someone asked me how to unlock or find the secret monster girl on stream i would be rich by now.
They where 3 things going around as DC Trolled ppl on stream before they even got implemented into the game.
1. A Monster Girl ppl simply didnt find yet. (wasnt in the game back then at all)
2. A Trap. A Girl who secretly is a guy but the MC can date and fuck. (Still not ingame but ppl believe it non the less)
3. The MC and Erik will have a gay encounter and fuck each others brain out and that part cant be skipped or avoided as its part of the main story. (people still believe DC will add that...... god i hope he doesnt....)
Yet we rarely ban anyone or kick someone for bad behaviour even tough they bombard you with questions in sometimes nasty manner or even straight insult you if you tell em those things are not ingame. We are kind of completely useless on picarto ^^
Especially the picarto polls which most of the time are purely for his own entertainment show his trolling.
My favorite poll was
"is (I wont mention her name but ppl who are often in DC's Picarto streams know who i mean) gay?"
A: Yes
B: Yes
C: yes
D: What was the question?
The only real polls we get on picarto are small stuff like
"Size of Breasts" "Size of Areola" "Which Logo should the school have" etc.
We also get alot of hillarius polls.
If you had to choose in order to survive
A: Suck a guys dick.
B: Cut your own dick off.
C: Get fucked in the ass by a big black cock.
Or one of the best.
Would you turn gay for money.
A: 10 Dollar
B: 1000 Dollar
C: 10.000 Dollar
D: 100.000.000 Dollar.
In terms of Trolling DC is at a grandmaster level with his audience ^^