drawn by my bro  altered

I exploded into change, wincing and trying to keep my stance as muscle and mass erupted from their mysterious source, making my clothes clench and strain against me in seconds. My jaw and sinuses crunched and stretched, resulting in inhuman grunts and moans of discomfort.
I felt my tail fill the seat of my pants, the pangs of the transformation making it involuuntarily thrash about in my shorts...

My dimly opened eyes reflected my mental state. My body was violently mutating into something beastial and my brain was simply going along for the ride, surfing among the primal chemicals being released in my shrinking cranium.