Backstory
Matia was once human with his sister, having lived at least 9 lives before Isiktan had decided to take the two twins under their wing as underlings, granting them a spiritual status as Incarnates. No longer reincarnated, Matia was able to recall all his past lives now, yet he never felt that any of those identities were "him" except the last one he had, the one who's appearance and personality he retains the most. Still, that won't stop him from recalling the details of the prior ones with his sister, Maite, the only person who knows him better than anyone else would. Isiktan would have had the opportunity to review their lives and remember the information, but to be a judge of his feelings, his humanity, only Maite could relate to him on that personal level. After all, even after they've passed away and begun their long after life, Matia still felt strongly like he did as a living human.
Assigned to go on excursions on Isiktan's behalf, to investigate trouble that gets in the God's way, to eventually accompany Gingko's group, Matia took the jobs with stride. He could do a lot of communicating, he could be of use, he could busy himself for the most part. If they were to capture all of the evil Gods running around, he didn't worry that Isiktan would no longer need him, he could simply retire and relax until the next catastrophe in the future. The Divine world was an interesting one to him, where he could meet other spirits, humans whisked away, and communicate with a God or two if Isiktan didn't want to. Essentially, he was Isiktan's right hand for any task.
Traveling with Gingko to search the ruins of the vast Divine world, following the whereabouts of the Miseries, there is a ghost that Matia ran into that caught his eye, a simple spirit who's dipping her toes into the matters of Gods. Both searching for the scattered Pandora's boxes, Matia ran into Paris, a comrade of the Misery Ephialtes, ultimately someone troublesome. Paris was admittedly clumsy and unsure of the task she was following, considered an enemy of Isiktan if she was working with Ephialtes, but Matia ran into her on enough occasions that he knows she is no harm. In fact, the two of them have so much in common (to Paris' dismay) that Matia wanted to befriend her; both had figures they considered sisters to protect, both were amusingly stubborn, and Matia figured out that Paris and her comrades actually have the same goal to defeat Merikh and Pagule. Of course, Isiktan and Ephialtes despising one another wouldn't make an alliance easy, but it'd be a great idea to team together. Matia knew it wasn't simple, but he'd at least try to get Paris to work with him to some degree. While she was prickly and dismissive of him in the beginning, he'd earn sides of her she hadn't shown others before, frankly charmed by the spirit.
Thus they crossed paths a lot more to Matia's delight, excited whenever he could see the ghost he'd fallen for, someone difficult who's something of an aquired taste in the eyes of others. Even she found him annoying, after all only bumping into each other when she was busy trying to find Pandora's boxes. When all was to be settled in the future, when Merikh and Pagule are sealed away, Matia would ask what Paris did intend to do for the remainder of her after life. Paris's own goal was to separate her human cousin from the Misery that possessed her, to free her of a curse, but her cousin deserved to go back to her normal human life. For Paris who passed away, she'd be in the way, so perhaps the Divine world suited her if she could make other company. Matia was one to extend his hand, having mentioned to her that if they have a long after life ahead of them as spirits, he wouldn't mind spending it with her. It was something that'd fly over her head in the moment, brushed off, but it's an option for the two one day.
Matia considers himself a patient person, although he really isn't, his sister Maite always telling him he's stubborn when he thinks he's on the best track. Although she knows him so well, he's been paying attention to her less, unfortunately not knowing his own sister as well as she knows him. During the journey to collect the boxes and fight Merikh and Pagule, before he knew it, Matia's sister ended up on the side of the culprits, swayed to do their bidding. To fight against his sister, perhaps he's the only one who could match up to her, yet truly behind her thoughts, nor would he want to hurt her. He retained his happiness by surrounding himself with others, yet she'd lost hers from their branching fates, something he feels responsible for by not noticing the toll. Isiktan could tell from the start who was fit for what, not surprised but disappointed by Maite's betrayal, but it weighed heavier on Matia's mind. If she was a step in the path of defeating the evil Gods, she would need to be dealt with as well, a thought Matia doesn't like to think about.