Demonic juggle balls

As I kept cumming, her belly go bigger and bigger. She groaned a bit as I finally pulled out, dropping her on the ground with cum leaking out of her gaping pussy. I wondered for a moment what I should do next. Maybe turn back into my tentacle shape. But then I could hear my master's voice again.

"Use the contents of the bag," he said and I noticed a bag lying next to me on the ground. A bit of black smoke was emerging and as I reached in, I could feel some round objects. I pulled one out and grinned. What seemed to have been juggle balls, but now seemed to be made out of black obsidian, with some flame in the middle. It wouldn't burn her, I realized, but it was part of claiming her for my master.

I grabbed the jester girl and started to push one of the balls against her ass. She begged to stop weakly but with another groan, I managed to push the first in. Her eyes rolled as I filled her backdoor with the balls, then moved over to her pussy. My cum leaked out as the balls went in, filling her stretched belly until I could see the outlines of them through her skin.