I have a four year old, yes, he can be a bit annoying, naughty etc just like any four year old. But as an adult he never knows if he is getting on my nerves, as it’s my job as the grown up to make sure he doesn’t know.
Five nights is a bit much, I have been with my boyfriend a similar time to you, he stays over once a week, however if there is a big change that week then I play it by ear and sometimes cancel him staying over. Yes, when that happens we’re both disappointed, but no ones pissed off or grumpy about it.
My boyfriend probably finds him a bit annoying sometimes, but he doesn’t show it and he certainly wouldn’t moan about him to me. When he comes over he makes a point of playing with him for half an hour, then essentially keeping out of my way until my son goes to bed so my son doesn’t feel pushed out.
We’re going away at the end of the month for two nights, I’m not sure if that’s a bit soon for my son, so I’ve booked an airbnb, that way if it’s too much for him we will have our own little apartment to escape to without my boyfriend. Yes, he will be upset if that happens as it reduces our time together, but he wouldn’t be an arse about it as he isn’t a selfish idiot.
I would happily move my boyfriend in today, but I chose not to have that sort of option when I chose to become a parent.