This could be for several reasons. Internal bleeding is one of the scarier ones. If it's a female, cysts could also be the problem. In any case, take it to a vet immedietly. Your pet's life could possibly be at stake.
Hamsters are warmblooded.
If they are adults, you can identify a male by his testicles. If they're still young, you can tell the sex by the distance between the anus and the urethra: shorter on females, larger on males. Sometimes hamsters lick each others bottoms prior to mating. If you don't want baby hamsters, I suggest you separate them.
Blood blisters on hamsters should be treated by a veterinarian. The vet can drain the blister safely as well as find out why it occurred.
Bottoms up
it means hamsters hate you
no they don't…. if blood does come out that actually means they are sick.
they can get really mean if you hurt them
It could be a urinary tract infection.
Maybe its none of your business to know DUMMY!!!!!!!!
there ancestors sleep at night Os they can avoid predators it works too. pet hamsters have the instit to do in their habit.
I don't know if you mean robot hamsters literally but if your saying "robo" hamsters they are great hamsters. I have 2 of my own. They are so energetic! And they haven't bitten me yet. so i Know they are the best u can get.
Get very territorial