I wrote this octogirl TF as a quick experiment to get a sense for how the changes might work. Explicit.
As I draw the water for a bath, I lean over the tub and squeeze a few drops of blue octopus ink from an eyedropper. They hit the water and billow out into columns of ribbon that drift in the flow from the spout. The little plumes remind me of jellyfish, which have always given me the creeps. The bottle says two drops, but last time I barely felt it, so I do four drops to make sure, then set the bottle and dropper on the edge of the tub.
I just want to relax for a couple hours, but in the back of my head, I keep telling myself I should be doing something productive instead. I strip off my clothes and toss them into the laundry hamper, then kneel down next to the tub and swirl my fingers through the water, until it's blended into a solid, bluish color. I flick the water off my fingers and look down at my reflection. There's nothing wrong with wanting to feel good for the rest of the evening. To keep myself from chickening out, I plunge right in, slipping over the edge and splashing down into the water.
The water's hot at first, but it's not hard to get used to it, especially as I lie back and settle in. It's only high enough to come up to the tops of my thighs. The flow from the spout douses my toes as I stretch out my legs and lean against the back of the tub.
It's hard to tell when the changes kick off, because I start anticipating the feelings before they happen; the warmth of the water soaking into my skin, my muscles tingling as they stretch. The easiest way to tell is to watch my legs. After a minute, the blue ink starts to seep in, leaving its tint on my skin. When I lift my legs out of the water, I can make out new coloration emerging: lighter along my inner thighs, darker along my hips.