After Melly was imprisoned, Cherta went to her cell and offered to bring back her powers. Once the two of them talked, they became friends and fell in love with each other. Cherta vowed to protect Melly. He even told the Creator that he will be responsible for Melly's action since no Magic can be done without his permission inside the castle. But because of an unexpected twist of fate, Melly changed the time and made March 1 into February 29.The consequence of Melly's magic was Cherta's time being stopped.
It was confirmed in Season 2 that the Yeohadan Captain was Certa. It seems that he does not remember Melly or any previous events regarding her. He has the mana ability "Nine", which is the same as Hiasen's.
He seems very distant and intimidating on the outside, but we see his soft, kinder personality when he becomes Hiasen's friend and mentor later on during the La Luna Arc.