Things were happening a bit too rapidly for Eric to keep pace. He was relieved to find out that Amy was still his girlfriend, but still trying to figure out (in this reality) he got to Kim's house. When she got irritated with his distraction with his phone, he had finally had enough. Time to undo all of this nonsense and get back to Amy. First things first: he needed to undo having a kid with Kim.
"I'm the father of Kim's kid," Eric muttered. He felt the ring tingle and was relieved to know they would no longer have a kid. Except...somehow Eric found himself looking _out_ the front door instead of _in_. The young man standing there had a very familiar appearance: dark hair, gray eyes, somewhat athletic build...and a face that Eric was used to seeing every morning in the mirror.
"So, Kim, are you going to let me in?" the man said.
"Um..." Eric froze in shock at the feminine tone of his voice - the exact tone of Kim's voice. He looked down at himself...and realized he was no longer a _him_. The ring had evidently decided that the lie was just in Eric being the _father_, so now he was the mother: Kim. He was even wearing the clothes she had been wearing, a simple light blue blouse with a swooping neck; from this angle, he could see down into the cleavage that was now his own.
The smart thing would have been to quickly close the door, lock his clone outside, and figure this out, but instead of saying no Eric shrugged and said, "Sure." It was just strange enough for him to take notice, and then he saw it: the ring was on the new Eric's finger.