In 2019, a work colleague of mine was diagnosed with Type 2 diabetes, and the doctor asked her if she'd be willing to go on a free one-day diabetes awareness course in a room at a rugby club. She agreed.
My colleague is a very quiet, timid little mouse; there were a few others on the course, with her doctor and a dietician.
My colleague told me she had a great time; it was a brilliant course, the doctor and dietician were great, and all the other students were fantastic, apart from one bloke who just HAD to be the centre of the universe. Very loud voice, kept interrupting others' conversations, even telling the doctor and dietician off because they asked him to keep his voice down and let others get some words in!
Apparently he was like it during break times too, wouldn't let anyone else speak ''without his permission ".
Every one of the students were trying to learn about their condition but couldn't concentrate because of him.
Back from the break, the dietician was trying to explain something, and Mr-I'm-Full-Of-Myself kept talking over her, very loudly, and my colleague, as quiet and mousey as she is, surprised herself and everyone else by snapping at him quite loudly ''Oh, Peter, will you just SHUT UP? BE QUIET! LET EVERYONE ELSE SPEAK AND CONCENTRATE!''
He shut his gob for 5 minutes then carried on, but at least he then knew everyone was sick of his ego!