You finally have everything you always wanted. You're not human anymore.
You rub your new body up and down. It's perfect, slender, and shiny, and it's all yours. You've got a small access panel in your lower back. It contains your SRPI port, some status lights, and your power and reset buttons, all locked up with a key hidden in a place only your girlfriend Liz knows about. Even you can't get in. You're designed this way so a stranger can't change your settings after they have been set and the panel has been locked back in place.
Everything about you is data now, your personality, your voice, your ability to feel pleasure or pain, it can all be modified. A piece of software that came with your instruction manuals allows you to switch between modes via an SRPI cable plugged in to the port behind your locked panel. You and Liz try out a few of the available modes. You came with the typical "maid" and "chef" modes, but Liz has something different in mind.
Liz has a firmware update for you that allows her to enable custom, more dangerous and fun modes than the ones that come pre-installed. You're assured that the update is perfectly safe, and you agree.
Early on in your relationship, Liz decided she was going to be in charge. Something in your rational mind told you that you didn't actually want that, but basically every other part of your body told you you did. That's when you discovered that you were submissive, and since then, she's been in charge of most of your life. The first time she took you out with a remote-control vibrator inside of you, you felt closer to her than you ever had before. You remember when she tattooed her name into the skin of your old body, before the switch, without telling you what she was writing. It was electrifying. But this is the most intimate thing she's ever done to you.
Liz gently lays you on your chest and asks you to stay perfectly still, even the smallest mistake could corrupt your firmware. You're not sure if you want to go through with this, but she insists, and with her behind the controls there isn't much you can do to stop her anyways. You feel your system temperature rise all over your body as your emotional response system kicks in. You're not sure you would ever stop her, no matter what she did.
You hear her tapping away at her computer, which is still tethered to your back. You feel a tingle running through your entire body. It feels like a mild electric shock. Suddenly your vision goes blank and you start to panic. She puts a comforting hand on your shoulder and tells you to stay calm. "Installing Custom Firmware" appears in your vision, hanging artificially in the air in front of you. Then, the rest of your vision goes out, and all you can see is the text hanging in front of the nothingness, with a small progress bar that inches along the bottom. This is all you can see for the next 20 minutes while all of your core programming is being rewritten. When the status bar reaches 100% your vision flashes red and you begin to feel weak.