Sorta relevent here - a lot of gatherings I attend devolve into "sessions" of sorts - it just sort of happens. Usually everyone takes a turn, things bop around between chorus songs, instrumentals, etc.; including conversations, insults, jokes: except when one particular person attends. Then it turns into the "watch ME hour" - no conversation, no jokes, no shared songs, no chorus songs - 1 performer - performing.

the Wierd thing is, I don't think this person realizes what a damper they place on the gathering.