Raltaak was a very much the picture of a friendly, harmless country Vicar. Mild mannered and helpful. Liked tea and to read and play chess.
That is until it was time to do some serious work. Then he was a knife in the back. The one you would appeal to for help, and who would admit that it would be the "right" thing to do to help you, but go ahead and stab you anyway. It's also what made the betrayal more cutting.
He was an extremely knowledgable statesman and frankly, I don't know I would have survived those first years after I became aware of myself. It was Raltaak that arranged for the things I needed, took care of all the finer details. He was the one that brought humans in to adapt my tower to what I needed (a secure place to sleep; buildings for things like kitchens; living quarters for them all). And also everything that was needed to keep the place running.
He was also helpful when I brought Val back. Again, he took charge and helped arrange for Val's needs.
Later when I'd decided to act instead of waiting for each of my lives to end and be reborn again, it was Raltaak that I sent to the city states to negotiate treaties. (It's not his fault that not all of my Mazoku were as intelligent as he was.)
When Xellos ruined him... it hurt. Like losing a child, only more so. Both he and Rashaat were indeed like children to me, as well as valued and trusted confidantes and retainers. I created them; I felt it when Raltaak died.
(If you need an explanation for why I was so headstrong and hellbent on eliminating Lina, it was this: Raltaak was just the last in a line of my Mazoku that were ruined and destroyed in such a short time period. )
In the time prior to my defeat by Aqua, Raltaak served as liaison between me and my siblings. We didn't care for putting ourselves at a disadvantage by entering another Dark Lord's territory unless it was absolutely necessary, so our Priests did that. They carried messages and spoke for us. He had to know all the ins and outs of the protocols that needed observing. I know I sometimes frustrated Raltaak with my refusal to follow them, but he would never say anything.
Rashaat, on the other hand, as my General he acted to coordinate with the lesser ranks of Mazoku, as well as the lower ranks (ie cannon fodder). Just as Raltaak was damn good at his duties, so was Rashaat. He was a fierce fighter (of course he was), and could handle any weapon he picked up with speed and precision. Where Raltaak appeared to be mild mannered, there was no question about Rashaat's ability to fight. He was strong and fast; brutal and merciless. He commanded my armies of Mazoku during the war and it was his responsibility for seeing that all of our forces were in place before I made my assault on Ragradia.
When Val joined our ranks, Rashaat was the one that provided him with training (in addition to what I taught him). He helped Val build his strength and reflexes; he helped teach him what it meant to be Mazoku. All without question. He never said one way or another if he approved of Val being there; he just stepped up and helped train the boy.
I'm fortunate that I did not have to suffer through his destruction, too.