That means no social engagements whatsoever during the afternoon hours or Saturday or Sunday. If, by some hideous coincidence you have to be elsewhere for the duration of the match (and you have to have a Very Good Reason) expect him to be bored, miserable, itching to leave, surreptitiously checking his phone every 3 minutes and generally unable to hold a conversation.
2. Being ignored.
Don't bother trying to talk to him during the game. You won't get any attention. It's not personal. At best you will get a half-time cuddle.
3. Genuine sorrow and despondency when his team loses.
Be gentle with him, he is vulnerable and sad.
4. The happiest mood when his team wins.
Pure joy. Now is the time to ask him to do the washing up/to make supper/a little treat.
5a. Yes, he will want to watch Match of the Day as well.
5b. He will also play FIFA before bed.
(Gifs from giphy.com)