Growing and Shrinking Thoughts
As stated earlier the MC is either a guy, a girl or a futa. Futa's can be born futa or have operations to turn futa but said operations are extremely expensive. The MC can have one exceptional talent be it something like athleticism, creative talent, or something similar. Otherwise they are an average person who happened to survive a freak accident which gives them their power. The only thing that all MC must have is a love for size for them the bigger the better, what they like to have bigger...
Fetish