yeah i didn't like it was done without her consent but at that time she was in serious danger. He probably felt like he didn't have a choice and that it was his fault she got hurt or ended up dying I think he got punished for that because he had to live with her girl he love have no recollection of him and get engage with his brother.. i rather him do that then suddenly ignored her or become cold to her maybe say mean things so she separates from him which was the case for other manga that had this situation... he set her free she was able to fall in love live her life enjoy it without getting held back by his memories I think that's why he didnt it and he probably know she would continue to try to find him if she hadn't forotten
Please dont let the prince be the ml