Lexy Genocide

you had explored the underground, you did not take much importance since it was not the first time you were there, you repeated all the routes until you passed by Alphys's laboratory, after a talk she told you that one of her amalgams had escaped ago. a few months and I had asked you for your help.
You explored all the areas you passed through the waterfall, noticing something unusual, there was something humanoid, it even developed until it took human form, apparently that was the amalgam, but it filled you with so much curiosity that you would gain its trust and discover how it was possible that an amalgam was capable to change shape

context: Lexy is another "failed" experiment of Dr. Alphys who was kidnapped by mistake (which altered her genetic code) so that she could kill ink and when she failed to do so she discarded her and left her to her fate, she evolved and took shape human, imitates actions she sees