The Strange Case of Dr. Bendyll and Mr. Ink (Act One)

A Bendy and the Ink Machine alternate universe basing on Robert Louis Stevenson's Dr. Jekyll and Mr. Hyde (but I cannot promise this would be fully based, as I have merged some ideas from the musical, and from my own ideas).
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-In the Victorian English city of London, there was a man - a cartoon hybrid, who works as a medical doctor - who lived to make a second persona of himself - one that would help him do things without even knowledge of others. However, it goes too far when his creation - which was a monstrous replica of himself - makes his own rules in his playground, whilst slaughtering everyone in his wake. Now, will his creator do his best to destroy what he had made before time runs out, and it becomes too late, or will his created inner demon reign victorious in their fight for control?!
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ACT ONE: An event long before the transformations of a cartoon hybrid named "Henry Drew Bendyll". What caused him to make such an experiment, and why did he make that decision in the first place?
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