As I almost reach the ring out of the shadows something else scurries towards it, grabbing it between its teeth. It's another rat. It turns with speed and heads off into the darkness. Being twice the size I quickly give chase, no doubt in my mind you I catch up. But not knowing the layout of the dark tunnels I quickly find myself lost, the other rat having escaped.
I squeak in annoyance, lost in the grey tunnels almost a complete rat now without anyway of become human again.
To my disbelief my squeak its met by a quiter reply, and emerging before me in the half light is the rat. I squeak again, this time with joy, and taking this as encouragement it steps foward, its whiskers brushing against mine.
I realise its a female, something about its smell seems to drive my heart faster and excite my whole body. Even though I'm twice the size she doesn't seem afraid and edges closer. Not knowing why, and giving up my human rationality to some animal instict I scurry onto her, my snout wriggling against her wet fur. She turns her tail towards me and feeling my rat cock getting hard I eagerly mount her.
The tunnel echoes with our loud excited squeaks as I completely give in to the most basic of animal actions and get lost in the moment. With human worries tossed aside it feels like the most pleasurable thing I've ever done.
I climax, my seed flowing blissfully into her. I realise she's grown, her fury body know more natural then ever to rub up against. But I realise its me thats shrunk. I'm now a complete rat.