I looked up about that red liquid you can see in the foreground. Silkmoth pee. She also squirted some sort of tan liquid on me when I picked her up to move her off the cocoon and onto a paper roll. Don't know if that was more pee, or the pheromones I've read about, but it sure came out in a violent jet!
As a sort of sad follow up to the last silkworm post, one of those two straggler caterpillars died later that day. The other finally started spinning his cocoon, but didn't complete it. I suspect he's dead inside the partial cocoon he started, but I haven't been motivated to investigate inside it to make sure.