Get consent agreement for each user (not contact)

Hello,

I'm trying to get the consent aggrement for users.But if I have multiple users related to the same contactID how should I procced to extract the consent aggrement in order to indentify each user answer?

For Example,let's say on my pc Mary created first account and respectively ContactId then, John and Denis created an account from the same PC. So they are assigned the same ContactId But all 3 users answered separately to the Consent Agreement so how can we know what John answered and what Denis answered, in order to send him or not, marketing emails ?

Thank you