YOU SAID:

bob is the friend of bob but bob ain't is friend

INTO JAPANESE

ボブはボブの友達ですが、ボブは友達ではありません

BACK INTO ENGLISH

Bob is Bob's friend, but Bob is not his friend.

INTO JAPANESE

ボブはボブの友達ですが、ボブは彼の友達ではありません。

BACK INTO ENGLISH

Bob is Bob's friend, but Bob is not his friend.