I had hamsters as a kid. One time I put two females in the same box. The next morning there was one whole hamster, and one hamster that looked like it was put on a guillotine. Everything past the neck was gone, the other hamster at ethe eyes, bone, hair etc.
When I was 14 or so I got a dwarf hamster for the first time, those things suck. They never learn how to be pets, they are fucking stupid and will bite you whenever u touch it even after 1 year. When it died I didn't give a shit, compared to the previous one, who was so dear to my heart, I use her name for my password to this day, only woman I ever loved