VeraCosyWomen's Classic Suede Memory Foam Slippers Anti-Skid Scuff with Warm Faux Fur Collar

I’m a size 5 which would be the best option for me to buy?

Is there any leather material in these?

Would these fit a male uk8? Having a charity fancydress at work & need slippers for a male colleague. Also, can they be washed? We’re gunging him, lol

I take a normal size 6. Is it best to go for the 5/6 size of 7/8