If there was a virus that killed off 99% of men in the world, I think it would be interesting having so many wives. It wouldn't be easy though. I'm thinking 100 would be doable if they had low sex drives or got headaches all the time at 9pm at night.

There may be 10-20% of them that want sex each night.
I think I could have sex with 10-15 of them a night and have multiple orgasms. It wouldn't be good sex all the time and the girls would have to help each other to get off often.
Outside of sex is where things get complicated.