Chapter 1 (or if you don't want to use the app, old.reddit link)

A slight smile crossed Mike’s face. “Excellent,” he said. “We’ll start now. Finish breakfast, call out of work, and get your ass ready. We’ll start by training that. Skip the dildo, plug, and panties. You won’t need them yet.”
“Now? But I—“
He raised an eyebrow an almost-imperceptible fraction of an inch.
“Apparently, I didn’t quite make myself clear when I said you’d obey my commands. We can work on that, too. Now, do what I told you to.”
“Yes, Master.”
I quickly finished breakfast, showered, and shaved my legs and pussy. I went back to my bedroom and started to get dressed before I remembered that I didn’t need—no, wasn’t allowed—to. I looked at myself in the mirror, briefly allowing myself to admire my breasts before remembering that Mike—er, Master—was waiting for me. I grinned to myself, and walked back out of my room to the kitchen.
Mike stood up and walked past me. “Follow,” he said, as though he was used to ordering people around like this, as if it was nothing but another day for him.
“You know, Sarah,” he said, conversationally, “I always thought you were innocent and naive. I can see that wasn’t true, but I still think I might need to break you.” With the last two words, his voice hardened, losing any remaining gentleness.
I quivered and gulped, and followed him into his bedroom. It was tidy, the bed was made, and the only objects out were about half a dozen butt plugs of varying sizes and a paddle.
“On the bed, ass up,” he said, with that same firm voice. I complied silently, and heard him reaching for something on the dresser, but couldn’t see what.
I found out quickly, as I heard a rush of air and felt a sharp stinging on my ass. “Count, and thank me after each strike”
“One. Thank you, Master,” I began.
As I warmed up, he started hitting me harder and harder, until I could barely speak coherently. “Tennnnnn, thannnk youuuu Masterrr.” I felt strangely blissful.
Then he started hitting harder, so that it really hurt. “This is because you questioned my orders. Keep counting.”
“Owwww, eleven, thank you Master” I managed to say. He kept going until… “ow! fifteen, thank you Master.”
His voice shifted, became far more gentle. “Good girl. Next time, your punishment will be harder, but you’ve done really well for me, and I think you’ve learned a lesson, haven’t you?”
“Yes, Sir,” I said, feeling an overwhelming gratitude. He put down the paddle and laid down on the bed. “Come here,” he said, patting the bed next to him. He put an arm around me and started stroking my hair. I felt at ease. We stayed like that for a few minutes. His voice went back to normal. “Sarah, how are you doing? Is there anything I can get you? You don’t need to call me Master now, just Mike.” I looked him in the eyes. “I’m good, Mike. That was really really nice. Maybe some water?”
“Of course, Sarah.” He kissed my forehead, went to the kitchen, and came back with two glasses of water, handing one to me.
“Take your time, drink water, and remember to breathe deeply,” he said, in a calming voice. “And no rush, but when you are ready to resume your training, tell me.”
I sipped some water. “Honestly… I could start now… Master,” I replied, looking meekly at his chest and slightly smiling.

He grinned. “Such an eager toy, aren’t you? I can see why you want to be a free use whore. Get on all fours again, ass up.”
He stood up, and I followed his order.
I heard a bottle opening, and a squirt of something, then felt something very cold touch my ass.
“Do your best to relax, whore,” he whispered to me, before sliding a finger into me. I’d thought about anal before, but I’d never done it. I felt him pushing in, felt some pain, and then… wow. It felt so great to be filled there. He rotated his finger around, stretching me gently, then slid back and pushed a second finger in. This time, there was no pain. It just felt amazing, and I couldn’t help but moan loudly.
He chuckled, removed his hand, and … pushed it back in with what must have been a third finger. I was very relaxed at this point and moaned like… well, like the whore that I am.
“Such a good fucktoy,” he murmured, before actually removing his hand, walking over to the dresser, and returning with what had to be one of the plugs.
“You’re quite flexible, so I’m going to start you with the third-biggest.”
He squirted some more lube onto it, and gently started pushing it in. It was too much, I … I didn’t think I could take it! I couldn’t help but say, “ow, ow, o—ooooooh” as he slid it into me. He gently tapped my ass with his hand.
“Good whore. We’ll leave that in until lunch. In the meantime, I want to test your mouth.”
He put down a pillow on the ground and gestured at it. He didn’t have to say what he wanted for me to guess. I knelt on it and opened my mouth.
“Since this is my first time testing you, I’m starting slowly. Go at your own pace.”
I licked my lips. Cum always tastes amazing, and I couldn’t wait to get his.
I started by licking his balls, then gently moved to the base of his cock and licked all the way up until the tip, lingering there and making eye contact. He moaned, and stroked my hair gently. I opened my mouth and slid him into me slowly, letting my tongue move side to side as I did. I started to gag, and got maybe three fourths of his dick in me before it was too much, so I stopped and held it there, focusing on my breathing and trying to swallow my spit. I held it, and then came up for air.
“Fuck,” he said, as I swirled my tongue on his tip again.
“Good,” he said, firmly grabbing my hair, “now I know how far to push you to start.”
He put a few fingers around his cock, just to where I had to stop, and pushed my head down onto him. My eyes widened. I’d never been face fucked before. But his trick worked. I gagged, but it wasn’t too much. And he was fucking my face like a pussy. I could feel how wet I was getting, and without even thinking about it started moaning louder and louder. I fell into a rhythm, quickly breathing when he pulled my head back, and swallowing saliva and precum as often as I could.
I lost all notion of the passage of time. It could have been 5 minutes, or 50. There was nothing but my mouth, and his cock. I was in heaven.
Eventually, I felt him stiffening more, and knew what was about to happen—or so I thought. He pulled me off of him and started stroking himself. Before long, I felt thick ropes of cum landing on my face and tits. It somehow felt… right. He came for what had to have been thirty seconds, then said, “clean me.”
I leaned forward and licked his cock, very gently, until there was no more cum on it. He grabbed a phone, and took a picture of me. “This is to remind you of your place. Let the cum dry on you.”
I think I’m going to like the free use program, if it’s anything like this.