[A/N: The Cannibal in book canon is one of the three wild dragons in Dragonstone during and before the Dance. Everyone in the castle is aware of it and consider him a terrible threat, some have even tried to claim him but failed, their bones litter his cave. However, in the Show, it is not mentioned at all. (maybe he's one of the ones that Daemon mentions but nobody mentions a dragon-eater.) Also, Sheepstealer is in The Vale so there's that.
For the sake of this story, The Cannibal is still an enigma and mystery to the inhabitants of Dragonstone because there's still other wild dragons that don't necessarily approach near the castle.
Because there are other dragons outside of the Dragonmont, the Cannibal has no need to approach that area and he'd rather feast and chill by himself in the Mountains. So whatever book canon fact you decide to state, please note that this is a Fanfic, clearly there will be some differences. Of course, respectfully.]
(Aerion's POV)
"Lord Aerion." Ser Steffon said as I walked up to the door, "You're finally back."
I nodded, "Ser Steffon." I said as I was holding two spears in my hands, "How goes your day?"
"Well, the Princess has been worried sick about you, if you don't mind me saying." He said as he followed me while I walked through the entrance, "She even asked me to look for you."
"Quite the risk, Ser Steffon, having a Kingsguard venture in the mountains with dragons about." I told him
"Yes." He said, "But judging by your appearance, you had no trouble at all."
"That's the problem." I said seriously, "I had none at all."
"I see." He said, "The Princess asked me to escort you to the main hall, My Lord. Maester Gerardys and Ser Robert are there awaiting."
"Hm." I said, "Maybe a bit of scolding, eh Ser Steffon?"
"She did not say." He said
"Let us not keep my beloved wife waiting." I said with a chuckle
It was two weeks after my first encounter with the black dragon. Vermithor and I had tried every day to hunt the beast but to no avail. I have only had a few encounters with it. Once when I followed its trail and came across it while eating a dragon corpse, not one I recognized, smaller than the other ones I've seen. Another time when the gray and striped annoyance tried to attack me but ended up being attacked by the black one; it survived because Vermithor attacked it, forcing it to retreat and it escaped quite easily.
One thing is for sure; it ate the flesh of dragons, whether live or dead. But considering that it never once shown attempted to fight Vermithor, I can only assume that it's intelligent enough to know it might not win a battle against a dragon of its size. Maybe it could, maybe not, we'll never know. Its flames were green and hotter than I ever imagined but Vermithor did not seem bothered by it the only time we experienced it.
Not only that, it easily attacked the smaller green dragon, killing it in an instant and devouring its flesh. Also, it tried to kill the other one, the annoying grey one but failed because we were there, leaving it wounded. That makes me think that this dragon would only attack a dragon when it is absolutely sure it can win. Which makes sense that it might not have attempted to approach the Dragonmont, because of Vermithor and Silverwing, who are formidable.
Nevertheless, I have attempted to fell the beast but it is more elusive than the Greyghost. Well, maybe not, Greyghost slips away faster than I can even blink.
I entered the main hall, seeing that next to the map-table, Rhaenyra stood with Maester Gerardys on her side. Ser Robert stood on the other side, giving me a nod as I approached.
"My Princess." Ser Steffon announced, "Lord Aerion has arrived."
Rhaenyra looked at me, "Aerion." She said
I approached the table and set the two broken spears on it, "Princess." I said as I patted my sleeves, "You called for me?"
She nodded, "Ser Robert and Maester Gerardys wish to discuss this dragon problem with you." She said as she walked up to me, "They have shared some information with me."
She placed her hand on my chest, seeing that my clothes were filled with dirt and grime. She gave me a look, one I can easily recognize from a mile away; concern. This entire time, I would often leave without Rhaenyra knowing. That is because she would attempt to convince me not to venture out and stay inside rather.
"Is that so?" I said as I looked over at the Maester, "What do you wish to tell me?"
Maester Gerardys cleared his throat, "Well, My Lord, we would have informed you of this earlier if you had not ignored us these past few weeks." He said as he smiled slightly, "But Ser Robert and I have been quite acquainted with this....well, we call it the Cannibal."
Rhaenyra stepped to my side, holding my hand as she looked at them, "And you have known about this dragon eating beast for a time?" She asked as I looked at Ser Robert
"Well, Princess, we have never seen it in person." He said, "But reports over the years, even before your birth, respectfully, have claimed of a black dragon with green eyes, feasting on dragon corpses."
"We thought they were rumors only, but one night, a dragonkeeper claimed he saw a massive shadow chasing after the Greyghost." Maester Gerardys said, "And well, it swore it saw a dragon's corpse in the black dragon's maw, its green eyes filled with a gluttonous desire."
I sighed, "Yes, well, he's real." I said, "Cannibal, huh? Quite a simple but fitting name. He's been trying to feast on Greyghost for a while, hm?"
"Why has he not attacked our dragons then?" Rhaenyra asked
"We believe that the reason for that may be that our dragons are well, formidable enough to fend him off." Ser Robert said, "Or perhaps it is because it does not like the presence of humans and will rather avoid them. But one thing is for sure, Lord Aerion's dragon's presence might be a deterrent. For years, Vermithor has made the dragonmont his home and all kinds of dragons have resided near him. Not once have we had a problem with this one....well, until now."
"Well, Lord Aerion was in the mountains, far from the castle and the dragonmont." Maester Gerardys said, "In its territory. The presence of your dragon probably unsettled it."
"Hm..." I said, "It can definitely take most of the dragons here. The grey dragon with the white stripes, the one that got atop the tower during the storm. That one is larger than Syrax and more aggressive, it was attacked by the black one when it tried to attack us. This...Cannibal...he's got a natural instinct to hunt weaker foes."
"But not yours." Ser Robert said
"Aye, not mine." I said as I looked down, "That does not make me feel better."
"Perhaps we should leave this hunt for the time being." Maester Gerardys said, "You have not been resting well, Lord Aerion."
"No, I need to hunt it down." I said
"Aerion." Rhaenyra said
"No, I'm serious." I said as I pulled away from her and picked the spears up, "What if it decides to go after Arrax or Vermax? Or gods forbid Joff's dragon when it hatches? What if it decides that Syrax is a suitable meal? I will protect my family's dragons."
"Aerion, just listen." Rhaenyra said, "I.....Ser Robert, Maester....can you leave us?"
I saw as the two bowed slightly and walked past us, leaving the room as Ser Steffon did the same.
I felt Rhaenyra's arm around my waist as she pressed against my back.
"You are being too reckless." She said
"Not reckless enough..." I said seriously, "I cannot let this threat be."
"For years, Aerion, for years it has been in the island..." She told me as I turned around and faced me, "It has not been a problem to us..."
She patted my chest and gave me a smile, her beautiful smile.
"I don't want that thing near our family." I said looking at her, "What would you think will happen if one of the boys decides to take a ride and this thing just comes in and takes them in their maw? Arrax is a tiny dragon, when Luke decides to take him to flight, a simple bite will be more than enough."
She sighed, "I understand, dear." She said, "But please.....just take a few days of rest. You have been at this for too long without success. You've been gone for days at a time, coming back to replenish your food and water and replacing weapons. How long before you go through all the spears in the castle?"
"Rhaenyra..." I said, "I...."
"It's okay." She said, "Take a bath, eat something....and come lay with me in bed tonight....we shall discuss many things that have happened in your absence..."
She patted my cheek before pulling away and walked off.
I watched as she walked out of the hall, leaving me alone in front of the table.
I sighed, "If you command it..." I muttered as I looked back at the table, "Hm..."
"Cannibal, huh?"