What are the limits of the relationship between a fiancé and his fiancée before the marriage contract?

The questioner : All right, Shaykh, regarding the matter of the engagement, is it permissible for the fiancé to sit with his fiancée in seclusion?

The Shaykh : No.

The questioner : It is not permissible!

The Shaykh : It is not permissible except after the marriage contract.

The questioner : Once the contract is concluded, she becomes his wife.

The Shaykh: Yes.

The questioner : All right, what are the limits of the relationship that exist between a fiancé and his fiancée?

The Shaykh : There is no relationship.

The questioner : Nothing at all?!

The Shaykh : Like a stranger, like someone who is not engaged.