Make her think she's my best friend swapped into her body.

I decided that I didn't want my mother thinking she had control. I had more important fetishes to play out. Instead, I whispered the code into her ear, making her think she was Jack, my best friend, trapped inside her body. She glazed for a moment, and then screamed.

"Calm down," I told her.
"How can I calm down, huh? I'm in your mother's body. Get me out of it."
"No," I said. "Now I can finally give you what you want and get what I want too--"
"I don't know what you mean," said my mother's body, in her approximation of my friends voice. But she drew in close to me. I kissed her and her hand went down for my cock.
She screamed again.
"What are you making me do?"
"Nothing you haven't always wanted. I know you dream about making it with me. That one time I woke up with your ass poked into my cock--"
"That was an accident--"
"Well, either way, you're a woman now, so why not enjoy it. After all, you need cum in every hole to change back."
"What? No way. You're not slipping it to me--"
"Fine, stay a woman, but remember I can do this to you." I grabbed her around the neck and watched her body shake with excitement. Then I bit at her cheek.
She whimpered and bit her lip, whispering "I need you inside me."
"What was that?" I asked.
"I need you inside me," she spoke up.
"That's what I thought," I said. I pulled her into a kiss, which she started to pull away from, but then pushed into with relish.
"Come on, Jack... uh, I mean mom. Where shall we start?"