All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
The consent and presence of the guardian and the presence of two witnesses are the most important conditions for the validity of the marriage contract. Any marriage contract which takes place without the consent of the guardian and presence of two witnesses is an invalid marriage. Therefore, this man is a marriageable man to you and you are not permitted to be in seclusion with him or allow him to enjoy you sexually. If any of this happened between both of you in the past, then both of you are obliged to repent and seek forgiveness from Allaah, and immediately stop doing so as he is a marriageable man to you [and not your husband]. For more benefit on the conditions and pillars of a correct marriage contract, please refer to Fatwa 83629.
Therefore, you are not married and there is no religious relationship between you and this man, and he is just like any other marriageable man to you. However, if he wants to marry you, your guardian must consent to this and two witnesses must be present.
Allaah Knows best.