Henri Blanc is the son of Jacques Blanc, his mother died in a car accident while trying to protect him. He has blamed himself for her death ever since, and carries a grudge against anyone trying to replace his mother, including Michelle Aubert. In the beginning of the game it is obvious that he and Michelle don't get along. However, as the game progresses, he starts to accept Michelle and becomes kinder to her. After Ako gets Jacques's wife's wedding ring from him she uses it to allow Henri to speak with his mother. It is then he comes to terms with her death and realizes its not his fault. After Michelle is attacked by a Genma, he cries for her fearing she is dead. When she awakens and tells him she's fine he asks Ako to go back to Jacques and tell him to marry Michelle, finally accepting her as his new mother.
Near the end of the game, when Jacques finally returns to Paris, he is attacked and killed by a future Ranmaru. Jacques, in a rage, attacks Ranmaru with his Oni Whip and kills him. As he and Michelle lie over Henri's dead body, Jacques's Oni Gaunlet sends its energy into Henri and revives him.
He seems to be able to know or feel when Jacques is in trouble or needs help, due to a telepathic feeling he has, this is never explained in the storyline.