Innocent Devil, Naughty Angel

For a long time I've thought I have the best girlfriend. Monica is short and slim, with lovely curvy hips and boobs surprisingly big for her small body. She has black hair and blue eyes. She's sweet and kind, and very affectionate, but she's also very shy. I love her voice and her gentle gestures, and also her moans when I fuck her. She calls my name "Julie!" so lewdly, so adorably.

She's not a futanari, but I am. I'm medium height, brown hair and green eyes. I'm slowly sliding on the chubby side, which helps me have huge boobs and nice thighs. Monica loves hugging me and pinching me all over my body, and she also loves riding my 6 ¾-inch cock.

Monica isn't much of a perv, so it's usually me who initiates sex. She's quick to get wet and to cum, though. She's the fastest-cumming girl I've known! I sometimes surprise myself fantasizing and masturbating while imagining her being taken by tentacles, or being gang-, or being fucked by her big sister. Things that she'll never do, but I kinda want her too. I wonder if she's just too shy to let her lust demons out.

Despite all that, I've felt Monica has been acting weird for the past couple of days. I invited her to my apartment for some lovely time together. She seems fin, and after some minutes she's already kneeling between my legs. She's gently stroking my futanari cock and slowly sucking my glans. I can see she's a bit doubtful.

"Babe?" I venture. "Are you okay?"

She tears up a little and takes my cock out of her mouth. Her hand stops its motion, but remains holding my hard dick.

"I... I've got something to tell you, Julie... Something... Horrible."

My heart skips a bit. I look at her, my worry evident in my face.

"What is it, Monica? You know you can trust me."

"I... I did something horribly wrong. I... I cheated on you."

I feel my heart stopping altogether. I take several seconds to react.

"What?"

"I'm sorry! I'm.... I'm so sorry! I regret it so much!!"

"When? With who? How??" I demand an explanation. For a second, I wonder why I ask her how. Do I wanna know how? I mean... She cheated! Then... Why I feel my cock isn't getting less hard?

"I know I messed up big time, I... I'm sorry..." She says as I look daggers at her. She swallows. She's absolutely nervous. "I... You know how there was a little party at Jessie's? She invited just a bunch of friends because of something about work. We had fun and dance and... A little wine. And there was this friend of Jessie's, Marie. They... go to the same gym. She was tall and... Strong and... She made great conversation and..."

I ask a simple question.

"Were you drunk?"

She looks down.

"I was... Drunk enough."