Aah, that’s tough! We’ll talk about Rathdenek though, since’s he’s been mentioned more. 

For starters, he’s a rather large black dragon. I doodled him once here. 

Personality wise, Rath is pretty grumpy generally. He’s skeptical and unconvinced by most superstitions, and likes to investigate such things himself. As a dragon, he believe’s he’s seen most things worth noticing, but privately likes to be proven wrong. While he’s not as cryptic as my other dragons, such as Nahlotmarok, he still finds himself getting off track every once in awhile, when discussing the things he’s seen to Cirvinde. 

Rathdenek’s awakening happened in southern Skyrim, not too close to Falkreath, but within that area. Being naturally solitary as dragons are, but not interested in dominating anyone or anything, he flies south and lingers here and there as the Dragon Crisis rages on. He secludes himself to various islands off of the coasts of Hammerfell and Valenwood. Rath picks up on random goings ons here and there as they happen. Learns of Cir’s growing popularity, but isn’t interested until after Alduin is defeated. He’s almost offended a mortal could outdo a dragon, especially one such as Alduin. 

Needless to say, a challenge or two later after learning the Dovahkiin actually resides in Valenwood often times, it’s not difficult to track him down, test his strength, and be utterly floored at them being evenly matched. Of course, Rathdenek is still a massive dragon, and the fight ends with him pinning Cir. Out of curiosity, the sweet boyo is left alive. 

There’s a...weird spark between them, like something has been missing, but both sort of ignore it because that’s weird. Rathdenek ends up following Cir around along with the other dragons here and there, but he’s the most loyal. 

Rathdenek 

A dragon who awoke during the Dragon Break, but his favoring the sea drove him from Skyrim early on. Before, he often inhabited small islands along the coast of Hammerfell and Valenwood, before they even were. After awakening, Rathdenek made his way into a heavily jungled island off of the coast of Falinesti, Valenwood. He dwelt there for some time, reveling in his solitude. Even when Alduin was defeated, he shunned other dragons that picked up on his scent and scared them away. 

It was not for some time that word reached him of a mortal, elven Dovah. Like many other dragons, he wanted to test himself against such an insult to their kind. The idea of mortal men harboring dragon blood displeased him, as it did many years before. 

When Cirvinde is travelling back from Skyrim to his home, Rathdenek ambushes him. In repsonse, Cirvinde single-handedly takes him down and essentially makes a bargain for Rathdenek to join him. He agrees, and it all goes to hell from there, because something clicks for them both and no matter how much they argue, they dislike being apart for too long.

Sivaadezek

Another dragon that becomes a part of Cirvinde’s inner circle. She dwells in the very northern parts of Skyrim, close to Morrowind. More docile than the other companions, she merely showed a quizzical interest once Alduin had been defeated. Seriously more amiable, although not tame. Had no issue eating people that came too close to her dwelling. A nice lady-dragon, though.

Rythe Avandus

Cirvinde slammed into the ground, gasping for air as his back hit the dirt and rocks and tree branches below him. Sharp edges dug into his shoulder blades, but the adrenalin kept the pain at bay, even as the dragon’s heavy paw pushed into the bones of his ribcage. The ocean waves roared somewhere behind him. He could hear the twigs snapping beneath the weight between thick rasps for breathing room. The world spun, and he struggled to blink away the dusty sand from his eyes. 

“You.” The low voice rumbled, practically rippling the blood within him at the depth of the syllables. 

Cir’s throat was raw, but it did not stop him from biting out, “Yes, me.” 

Dovahzul came so naturally now, almost more so than his mother tongue. 

“You may be the Doom of the World Eater. You may be us in Soul, but you remain very small and quite breakable.” Rathdenek sneered. He bared his teeth mere inches from Cirvinde’s face, breath as hot as a bonfire fanning over his skin. It lasted for only moment, as the dragon lifted his leg. Yet he stood hovering over the much smaller figure, who couldn’t help keeping the feral grin, decorated with laugh lines, on his face. 

Many years ago, Cirvinde would have pushed such things aside for a more soft, friendly approach. Here, at the edges of Valenwood, with the gloomy, treacherous sea sprawled around them, the chilled air made him feel more at home than he ever had. And he was confident, and he was sure. 

“Yet you keep me alive,” He called while Rathdenek hovered by the seaside, folding his wings delicately back into his body. “You haven’t killed me yet, no? There must be a reason.”