Slang for the complete and total personal isolation one is required and expected to maintain upon being diagnosed with COVID-19.
He retreated for six weeks, just to be ultra-careful, to his comfy COVID cocoon and played video games while receiving meals every few hours, Door-Dashed from his favorite restaurants, left like clockwork at his front door.
When someone excludes themselves from society and attempts to improve on a certain factor of themselves such as a particular skill, their personal appearance or an assignment so when they're done they feel like a beautiful butterfly.
Person A: "Is Andrew coming to the party?"
Person B: "Nah he's cocooning."
Person A: "What for?"
Person B: "He's trying toget in shape."