Musing on the thoughts of "How Many"
With some Hamsters, it's a Single Life.
Most other Furries it's 2+.
With guineas, it's 2 boars (without females stirring things) or a neutered male + females, but not two males.
Rats seem to be a bit more civil.
I had 2 sows who were very much independant creatures (which was good) but the remaining one was very intolerant of cuddles. But she'd saunter round like a little dog indoors, at our heels 
I've had 4 sows at once who functioned as two distinct pairs (Mum/Daughter and Mum/Daughter). Any attempt at intergration was met by the oldest sow with a definate "No"
Once she died, her adult piglet was able to get on with the other two and they moved in together.
My currant set-up is a neutered boar that we got as a tiny piglet for our bereaved boar. They were together a year until the 'piglet' was bereaved. We side-by-sided him while he was neutered and waiting.
It's a really nice group, he's very protective and thinks he's in charge (ha ha!). He rumbles round and gathers his wives to the veg plate. But IRL, they are in charge.
The bigger sow is very laid back, the little one is much more 'bolshy'. She'll just bulldoze through him and he lets her.
I'm hoping they'll all grow old and grey together (all the same age).
I'd never have considered three TBH, but it works nice with them.