You give Jace a dream he will never forget.

It all started one day after your training.

After a few hours of hard exercise you, Neir and Jace finish up for the day.
"Mell, There is something you should know..." Jace says.
"What is it, father?" You ask.
"You and Neir will have to do without me for a while."
"Why is that?"
"I've got a big fishing trip coming up. Spawning season is coming up and we have to take advantage of that if we want to pay the kings tithe this month."
Ah, the wretched kings tithe. Every month, the citizens are made to pay a sum of Gil to the capitol or face the consequences. From what you've heard, the amounts have been getting high every year.
You wish him luck and he gets on his way, preparing for the two week voyage.
However, Neir whispers in your ear and gives you a positively dastardly idea.
You are going to fuck your father.

It is midnight when you sneak inside of Jace's room. It's dark, but you are accustomed to seeing in shadowy places. Jace is fast asleep, spread out on his bed with only a pair of breeches to cover his body. He is quite the handsome man. His years in the guard and on the seas have given him powerful muscles. This should be fun.
You slowly pace toward his sleeping form, Neir following behind you. Their isn't a scrap of clothing between you. You crawl up onto the bed, kneeling between his legs. You curl your dainty fingers into the band of his breeches and pull down, unveiling his girth.
His cock is quite sizable. Not the biggest you've ever seen but good enough to satisfy you. You lift it up and hold it against your forearm. Seated on a nearby table with her fingers shoved up her cunt, Neir nods in approval.
You start by sliding your tongue down his length. It tastes salty, like sweat and ocean air blended together. You suck him slowly, only doing the tip at first.
Jace stirs but doesn't wake. A moan escapes his lips.
"Ohhhh..."
"Colline..."
Oh, my. Who is Colline? Mell's mother perhaps? Or some flame from long ago? Who knows.
You take him deeper into your mouth, almost all the way. You almost gag on it, but that is a new record for you.
This makes Jace stir all the more. His eyes flutter open. Through narrow lids, he spots you. Or more specifically, he spots his daughter with his dick in her mouth.
Groggily, he says, "Ughhh... Mell...?"
Before he can fully wake, you pop his cock out of your mouth, hold out a hand and say "Trance!"
His head falls back onto the pillow as white sparks shoot from your fingertips and circle around his head. He enters into a, well, trance. It's a simple spell, meant to ensnare a persons mind and make them suggestible. The sparks dance around him and his pupils turn into stars.
You climb up him and sit on his chest. You look him in the eyes.
"Hello? Father?"
"Ya might've overdid it a little..." Says Neir.
"Oh, hush." You snap back.

Jace suddenly sits up. You slide back a little, his erection sliding comfortably into the cleft of your ass.
"Oh, here we go!" You say in excitement.
Jace grins and whispers to you, "Colli, be quiet! We don't want to wake the girls do we?"
He grabs two big handfuls of your behind.
You grin right back. "No. No, we do not."
He grips your waist and lifts you up, positioning you right above his cock. He doesn't bother easing it in, he just slams you down onto his cock. You cry out and immediately cover your mouth.
Neir says, "Careful! Don' wanna wake Yuna..."
"Yes, yes..."
Jace pounds you steadily. His cock is thick, stirring you up inside in a way that you haven't felt in weeks. You moan through your hand.
"Oooh, Neir, you have got to try this, he's wonderful!"
You quickly finger your clit, pushing yourself to cum. You manage to pull yourself off of him, his cock turgid and dripping from your insides.
Jace says, "Colli, what's going on?"
You trace a finger down his chest.
"Baby, can you give my friend some loving too?"
He weakly says, "Okay..."
Neir climbs up onto him, in reverse. She sits down onto his dick and lets out a satisfied groan.
"Ohhhh, yeah, that is mighty fine..."
Jace starts pounding her, putting his hands on her hips. She bounces on top of him, her tits bouncing along with her. You pull Neir in, kissing her deeply. You curl a pair of fingers in your cunt, coaxing more pleasure out of you.
You pull away and drop down, getting up close to where Neir and Jace's bodies met. You suck on Jace's balls, savoring the salty taste.
But soon enough, his balls start to tighten. You push Neir off of him and shove Jace's cockhead in your mouth. Cum shoots down your throat. It feels warm in your belly. You suckle on it for a bit, making sure that he's clean before you and Neir get off the bed.

You grab hold of Jace's head. You lift the trance. His eyes flutter with a bit of recognition of your true identity before you say "Sleep!" and he collapses on the bed.
You and Neir hold hands and make to leave. However, when you open the door, there is someone there.
Yuna, your so-called sister, stares at the two of you with wide eyes.

"Mell...? What did you do...?"