Do I have to take a full motorbike lisence?

I have a 125cc CPI Hussar Moped and i have passed my CBT. To have a passenger on the back I believe I have to pass the full motorbike test. I was wondering if there was another way. I don't really want to learn how to use gears etc on a motorbike when I have a moped, it seems like a waste and I am happy with my 125cc as I only want it for me and my partner to go for a ride in the summer and for me to commute to work in between. Is there anyway or any other l(smaller) test I could do (maybe a restrictive lisence) that i could do which would enable me to have my partner on the back of my moped without having to go through the full motorbike test? Your answers would be greatly appreciated.