Young male is "marking" just FURS!!!

Hallo!
I have 8 months old boy-cat, he is not castrated.
We want to get breeding marks at the exhibition after 10 months and then will decide, to cut or not to cut
The thing is that he is marking just furs! the coat of goat, the sheep's hat...
and he does it after he meets his close friend small kitty (4 months).
Kitty is living with my, boy-cat is living with my mummy, sometimes i go to my mum with Kitty. After that the biy begins to mark the fur.
Is that because of feeling "female" ?
But why does he mark fur???
Thanx.

Must be something in the fur that is triggering a marking response or sexual response. I'd confine him to a washable room till you get him neutered.

I'm assuming this is a purebred cat you want to show or something? Not quite sure what you mean about the "breeding marks at exibition"????

GoldenKitty45
Thank you for the answer!
Sorry, english is not my native language.

I wanted to say that we would go to the cat show, to get ex1 ,etc))))
If he is good, we will use him in breeding..
Yes, he is purebred cat.

Ok - what kind? Just curious.

scottish straight male!