It made me think of the young man

The young man Pip is thinking of is 

Magwitch's fictional character.

Earlier in chapter 1, the escaped convict Abel Magwitch terrifies young Pip out on the marshes. Magwitch threatens Pip that he is not alone and that a fierce, cruel young man is hidden with him.  The mysterious young man has a peculiar way of "getting at a boy, and at his heart, and at his liver" to tear him open.  When Miss Havisham touches her left side and asks Pip if he knows what she is touching, Pip immediately thinks of the heart and the "scary young man" who threatened to get at his insides.