The scrolls led you to angel, showing you two glyphs moving around Nexus together. Nascent Blossom met him first, guided by his scrolls and also by his mentor. Leon Ardo followed noting the grouping of scrolls, and the even greater confluence brought Lotus to them as well.
Angel is nervous and guarded at first, and not much better when you get to know him. He has agreed to work with the four of you, seeming to crave friendship whilst being terrified of it. And because you share the goals of finding the scrolls.
He resents each of you. He seems most sympathetic to Blossom, a fellow outcast, and the one he has known longest. Not to mention that Blossoms methods seem most compatible with his own.
He seems to have an almost genuine hatred of Lotus, for no adequately explained reason. And shows naked contempt for both him and Arda. Yet he's been a loyal ally so far, and shows no hint of doing anything worse than dropping frequent insults.
He seems to have something of a vicious streak, and he'll frequently be a little reckless then regret it heavily later. He seems to osciallate between a positive moral outlook and nihilism. He remains taciturn for the most part however, and has said very little about his past.