A neutering. And no, I'm not being funny.
Usually because he is over excited and wants to play.
An unneutered/intact male cat is called a 'Tom' or 'Tomcat'.
No.
Are we talking UNNEUTERED male cats, and UNNEUTERED male rabbit? You are leaving yourself open for a lot of spraying. Neutered males should be able to co-exist unless someone has a dominant intimidating personality, which can't be determined until they are all in the house together.
An unneutered cat is a 'Tom', but once neutered they are called a 'Gib.'
male urine is the worst
Unneutered male rats are prone to buck grease, an oily orange skin discharge usually caused by an overproduction of testosterone
yes
Urine exits through the male's penis.
A male cat is usually called a Tom. This term is usually used only for unneutered males.
It is safe for a male to drink a woman's urine, or any humans urine, as long as it is in small doses and there are no toxins, such as dangerous medication, in the urine.
If the male has not been neutered and/or the female has not been spayed, then yes. And unneutered dog can get any unspayed female dog pregnant.