The only thing ruining this moment is the constantly spying demon lord.
He grew irritated and extended his spirit into his surroundings. His soul ripped control of the momentum of the surroundings from her. Then he cloaked himself in it. He finally has peace and quiet.
He sighed contently. "That's better."
Then he noticed that another thread of chaos was flowing into the flame on his crown. His act of usurping the control of the demon lord is against the order of the abyss so it created chaos to empower him. The result encouraged him, so he actively pulled on the momentum with the Chaos energy around him and fed it into his flame. The flame ate it up and began to grow faster.
He chuckled. "Even better."
Her control of momentum isn't as absolute as her control of the energy well. She is sitting right in the energy well, so he will have to move there to get it from her. Even then, he won't succeed unless he kills her or she gives it up.
But the momentum around him can be forcefully taken from her. Her flimsy control over it couldn't stand against the combination of his expert knowledge of momentum, and his powerful soul. He would have done it just to get some privacy and to spite her. The improvement of his Accumulation of Chaos ability is a bonus.
He grinned happily. "She must be fuming right now."
He didn't need to guess her reaction. She is banging on his domain from the outside where she still has control. Having part of her power taken is a great insult. Taking something that belongs to a demon of gluttony is a life-and-death matter. So yes, she is really pissed right now.
He let her regain some of her control. Her divine sense flooded in immediately.
"What have you done?" She screeched at him.
"Nothing. I am just admiring the lovely view of the abyss. Don't you think the plane is beautiful from this height." He answered nonchalantly.
"Are you mocking me?" She growled at him.
Her mood was affecting the non-existent weather on the plane. The scanty ashy clouds in the sky were agitated and lightning flashed through them.
He was still unbothered. "Alright. I admit I have done a lot recently. Which one of my activities has crossed you?"
She yelled at him. "You are playing with fire."
That isn't a threat to him. He has literally been burning ever since he became capable of movement. He is sure any fire that she can dish out cannot compare to the Chaos flames burning on his body.
Aeternus rolled his eyes. "Just say what I did wrong that has made you so angry. Then maybe I'll apologize."
He wanted her to admit that she lost control of her momentum to him or that he stole some of her power. Anything would have been okay for him. But Beelta couldn't answer. She stared rigidly at him while her emotions boiled. Of all the things that she might have considered the weird demon to be, she never considered him a threat. That might not be the case anymore.
He was supposed to be her prey and anything opposite to that was simply impossible and laughable. But recent events are making that prospect very possible. It hadn't turned her against the idea of eating him though. It had only made her want him the more.
Still, she recognized the rising risk that this weird demon is to her. It is not every day that demons of any kind usurp her authority from her.
"Well, I have places to be and things to do." Aeternus began flying.
Since she won't admit her loss to him, he had better find another source of entertainment. The divine sense followed him even though he moved faster than 5 times the speed of sound.
"You know I am the demon lord of this plane of the abyss right?" She asked.
Aeternus wondered out loud. "Hmm, so that's who you are. Who would have thought that the demon lord has a hobby of stalking innocent demons."
She ignored his jab at her and continued. "I control the entry and exit into the plane. I might not be able to do anything to harm you right now. That will change if you reach the domain of noble demons or if you leave the plane through the abyss altar."
"Let's cut to the chase. Why are you telling me this?"
"To let you know that there's no way out for you."
Aeternus nodded. "Hard to believe that since you said the same thing earlier and you were wrong. Do you remember that time when you planned my moment of desperation? I was wrong, you weren't a fool. Instead of waiting for my moment of desperation and then offering me help, you decided to create it yourself. Have I complimented you about that yet?"
"I know you're angry, but there's no way out for you. Unless you use one of the powerful tools you found in that ring, even then you won't be able to kill me like you killed those 300 high-rank demons."
Aeternus did not react to her mention of the powerful tool he used to kill the 300 high-rank demons.
He spoke calmly, "Right. You figured that since you're made of stronger stuff, I can't kill you that way."
"Yes, I am."
I never asked. What do you want with me anyway? What deal do I have to make with you so that you will leave me alone?"
"At first I wanted you to promise to do whatever is needed for me to get access to the chaos energy you have."
Aeternus interrupted her, "By "whatever," you mean even my death right?"
She ignored his question and continued. "But that has changed. In a gesture of goodwill, all you have to do is tell me all you know about the chaos energy, how you got it and what else is in the spatial artifact."
"Not a bad deal. Will you give me time to think about it?"
The demon lord spoke amicably. "Of course. I'll give you 10 years."