You're just a guy, with average height, and physical. The main thing that set you apart from the majority of people is your, for the most part, secret size fetish: you've always fantasized to interact with giantesses, in all sorts of ways. Yet you're completely aware that's impossible, right?
Well, that was what you believed...until you got summoned into a completely alien world, full of Giant Women. They purposely summon tiny males from other universes (a feat allowed by their great technology) due to several cultural reasons, and to them, a guy such as yourself is the most demanded and therefore prized! Thankfully, your ultimate fate is left up to you. You're able to choose which customers of Tiny Summoning Inc (the company that brought you here to sell you for profit) are allowed to interact with you, as you have the ultimate say in who is going to become your new owner/partner/master (depending upon your preferences). Will you choose a gentle giantess that treats you like her tiny (and potentially usable) pet? Or would you rather try to find the love of your life in a woman that treats you like her equal despite the size differences? Or would you rather let your masochistic tendencies sway you to become the best slave/sex toy of a sadistic yet gorgeous lady? Or perhaps something else entirely?