Train her ass...

As Riley's quivering, pale ass grows red under your kneading fingers, you decide to spread her cheeks to get a look at her little pucker. It's tight and pretty, with no hair and only a little bit of darkening.
"Daddy...." there's fear in your little girl's voice,"...what..."
"Quiet." You stick your middle finger into her mouth, and she obediently suckles, but there's a whimper in her throat.
"Riley, baby girl. Have you been letting boys stick their dirty little dicks in your ass?" You rub her knot with a thumb. "Tell me the truth, Riley."
"No, dahhy." She says around your finger.
"That makes me very happy, baby." You take the finger out of her mouth. It's soaked with spit, and you start to work it into your asshole.
"D...a....dddy....." she whines.
"Don't you want to make my happy, Riley? Isn't that why we're doing this?" You probe and rub, working her sphincter to get it loose and used to the insertion.
"I do....but..."
"Good." You drop the belt next to her face. "Do you think that Leah keeps lube anywhere?"
"Um...." Riley squirms.