Gabriola jellyfish with companion

At the end of a Gabriola summer, we often find dozens of jellyfish washed up, dead, on the beach. These are Lion’s Mane jellyfish — the kind you hope never to meet while you’re swimming in the sea.

They’re dead already when we find them on the rocks at Whalebone, right? So I took out my knife and sliced one open to see what the insides are like. (As one does.) Took some photos of sliced-up jellyfish, and then noticed this little guy in many of the photos later on. Who’s he, and what’s he doing there? Is he a parasite, a symbiotic companion, or what?