I took him to a shelter and let him choose. The first female totally dominated him, humping him angrily, chasing him around and pinning him down. Poor boy was terrified.
The second female he took a liking to... a bit too much. Starting humping, ripping out fur, she just sat and took it. When I tried giving some lettuce, Rascal boxed her away and wouldn't share.
With the third female, they pretty much ignored each other. Sat within a few feet grooming, sat together in the litterbox. Shared their veggies respectfully. It wasn't love, but it wasn't hate either. I thought I'd try it out.
They have never had a scuffle or disagreement. They're not very lovey-dovey, but they snuggle a few times per day, and give short grooming sessions. I have a feeling they are pretty evenly matched, in terms of dominance, so they're not quite sure what to do. But they get along and play and cause trouble together!
I'm really glad we went through that process. When I took them home I had a period where I kept them in neutral territory (my bedroom) and they had a "poop war" for almost two weeks, but then they were loose in the apartment and were totally fine. No nerve-wracking bonding sessions.