Hello guys, so I have another problem today, but this one is a major one. So I would be grateful to you all if you all could help me
. 
Let's have look at the sentence in set 1
1) (I called this a set, because it consists of many sentence, correct it if I am wrong please
)
He is just a friend of "mine".
He is a friend of John's.
They are friends of mine.
They are friends of John's.
The cuteness of dog's make me happy.
==> The problem is that I don't know which "nouns" I should after "of", possesive or normal noun ? As you can see it's very confusing if we take a look at the sentences in set 2.
2)
I am the soul of my body (why don't we say I am the sword of my body's)
It's the book of love (why not love's)
He is the Son of Zeus ( why not Zeus)
He is the god of the Sun ( why not "sun's")
He is the son of batman (steve
) (why don't we use steve's or bat man's here")


Let's have look at the sentence in set 1
1) (I called this a set, because it consists of many sentence, correct it if I am wrong please

He is just a friend of "mine".
He is a friend of John's.
They are friends of mine.
They are friends of John's.
The cuteness of dog's make me happy.
==> The problem is that I don't know which "nouns" I should after "of", possesive or normal noun ? As you can see it's very confusing if we take a look at the sentences in set 2.
2)
I am the soul of my body (why don't we say I am the sword of my body's)
It's the book of love (why not love's)
He is the Son of Zeus ( why not Zeus)
He is the god of the Sun ( why not "sun's")
He is the son of batman (steve
