Our playful day [MF]

Stories about roommates ending up fucking are quite common, aren’t they? Nevertheless, this story is also about roommates, about how I met her and how we came quite close.
A bit about me: I am a straight man. My roommate, as far as I know, is a straight woman. You may imagine how we look as you want to.
Well, how did we come to meet? Pretty easy: due to lack of affordable living space. I had to move to a new place for an unavoidable reason, and finding a proper place to live was just impossible. Even half decent apartments were beyond reason. My job wasn’t too high paying, and I needed to find a place to work from home and have a decent, friendly atmosphere. Fortunately, I had a friend and I got to share a room with acceptable prices, fast internet, peaceful neighbourhood; just a nice cosy little house. I was to share the house with a girl.
I met her one day, and she was really great! Somewhat shy, easy to laugh, great listener, very cute and overall an engaging person to talk to. We shared a love for reading and our talk moved to our favourite books. We had a great time and I had moved in the empty room. Apparently she had a roommate who had to leave due to circumstances. I felt guilty about the sudden envy that I felt.
“So, how was he?” I asked, attempting to mask my feelings.
“Oh,” she said, giggling, “it was a she. She is a good friend, and we had moved in together. But did I hear the tone right? My, are you already jealous?”
“Hey, I was just asking.”
I wasn’t just asking. I know I shouldn’t form such feelings so early on towards a person, but somehow she was just my dream girl. It was almost as if I was writing a fictional character, moulding her personality and interests to match my type, and who somehow develops feelings for me without me doing anything.
But that part comes later. We now spent months together. Our schedules were quite unchanging, so time flowed quickly. We did not have a lot of problems in our share of chores. Neither of us were very particular about what we want to do, so we just drew lots to determine who does what. I was a better cook, so I cooked more often. She was more efficient at shopping, so she would do that more often. We continued our platonic relationship for months. We rather enjoyed each other’s company, conveniently sharing a lot of common interests, and just being nerds.
Well, being nerds, our ideas on sexuality and courtship were rather skewed. What we did wouldn’t be quite common outside fiction, but it is what it is. We don’t know how we ended up talking about our sexual tastes, or, actually, how did we go for months living together without talking about that? Turns out, we both like each other, conveniently, and we didn’t want to just strip and start fucking. No, we weren’t that normal.
We decided on a rule: we won’t show our nude bodies to each other. This was, of course, temporary, as neither of us would be able to hold it quite for a while. Oh, and don’t ask why the rule exists. It’s my fantasy; I am the God here. But anyway, to compensate for this rule, we both decided to give each other a “task” or a condition that the other will have to fulfil for a certain time frame. Of course, the task shouldn’t break the no-nudity rule. How much nudity? Well, no part of the skin of the genitals must be seen directly, and after a brief discussion, her nipples shouldn’t be seen in entirety (partially allowed, yes).
For the first time, we decided to make it one week.
“So, what will my task be?” she asked, excitedly.
I thought for a while to all my weird fetishes. I wouldn’t disclose all of them, but I said-
“No bra.”
“Well, that’s easy enough. Sure you want just that?”
“No bra and tank tops.”
“Well what happened to the no-nipple rule?”
“No intentional flashing.”
“Well, I’ll try.” and she gave me a sultry teasing look. Damn, she can arouse me with just a few words.
“So, what is your task for me?”
“You’ll wear my panties for a week.”
“…”
“…”
“Pardon?”
“You’ll wear my panties for a week.”
Wow, that was unexpected. “Well, what happened to the no-genital-skin rule? I don’t think I can fit it into the panties.”
“Of course you’ll be wearing something over that.”
Silly me! “Yes, but… Actually, you know what, it might be an interesting experience.”
“And you- oh! Can we add one rule? Just one? Please? You can add one too.”
“Of course.” I’ll have her sit on my lap for an hour.
“You’ll have to return those panties with cum in them.”
“…”
“…”
“Pardon?”
“You’ll have to return those panties with your cum on them.”
Wha-? “Yeah I should stop that pardon joke, I’ve used it twice already. Anyway, your demands are very unexpected. What do you mean to do with it?”
“wink”
“What do you mean, “wink”? Don’t get pregnant with them.”
“I don’t think that’s how sperm work. You should know, at least.”
“…”
“Haha, don’t worry, they’re not going up my pussy.”
“…”
“So anyway, what’s your second task for me?”
I should probably add something related to this… “Okay, so when I am covering those panties in cum, you’ll have to be in the same room, and watching me.”
“But what about the no-genital-skin rule?”
“Yeah…”
We had a desk that conveniently blocked off just my crotch from the her view if we sit on the opposite sides
She said, “Let’s try it out,” and reached under her skirt to take off the panties that she was wearing. Hmm, black lace.
We tried it out, and I was able to take off my pants and underwear, put on her panties, and pull them back up without showing any private skin. The panties themselves felt weird. They were exceedingly soft. Of course, I wasn’t able to cram all my junk into them, so it hanged outside the panties and under the pants. Also it was erect. She giggled the moment I got up from the desk and blushed a little, staring all the while. So she actually likes it? I was a bit happy to see her enjoying it.
“Well, I guess I should change, too.”
She went into her bedroom, and came out a couple minutes later. She was wearing a tank top, as promised. They were called halter tank tops, I think? The type that hang from the neck, at least. And it showed ample sideboob, which are a weakness of mine. But as if that wasn’t enough, she was wearing the boxers that I had just switched for her panties. Oh, her fetish is to exchange underwear? What made me blush was the wet spot of precum in front. I had been aroused for a while, and whenever I am aroused, a lot of precum comes out. She touched the wet spot with her index finger- Aaah -and licked it, all the time looking at me. Stop! You’ll make me cum without touching. Thankfully, she did stop.
“Oh, your boxers are so comfortable~”
“Oh, and your panties are quite tight.”
“Oh, pull them to the side” glance
“They’re already pulled to the side.”
The next few hours passed normally. Well, quite abnormally in general, but nothing too wild came out of it. Just that she would stick close to me. Aah her scent is so bewitching! There were many touches, some to very sensitive parts.
I couldn’t hold it.
Three hours after we had started, I said, “I can’t. I want to cum.”
“Already?”
We had planned that the cumming-on-panties thing to happen every morning, just before we went to shower. But I was way too aroused to properly concentrate.
“Well, we did decide that you will cum only on my panties and only when I am around, so I guess we have to do this.”
I don’t remember anything like that, but okay. I am not complaining.
“Sigh… Okay, get behind the desk. You’ll have to wear new panties after that.”
I got behind the desk, and took off my pants and the panties. I took the panties, and put them over my erection. She sat down on the other side of the desk. Of course, she didn’t see or feel under the desk, but just the fact that she was so close and watching me closely while I jerked off was very erotic.
It didn’t take long for me to orgasm. The soft feeling of the panties combined with her looking directly into my eyes all the time, her heavy breathing mixing with mine, the view down her top… Let’s just say she was a complete Venus for me. I moaned as I covered her panties in my seed. After I had done, I pulled them from under the desk; the white semen looked great in contrast with the black fabric. It was dripping. She took hold of it, and as I had thought, started licking it up. Looking at her pretty tongue leaving her mouth, licking some of it, going back inside her mouth and returning fresh; it was a glorious sight. I burned it into my eyes.
She also burned it onto my tongue as she kissed my mouth after she had done licking most of the cum. Turns out, she hadn’t swallowed it; she was keeping it in her mouth for sharing, and share she did. It was a sensory overload: she had thrown herself at me, not completely, but her chest pressed against mine and there was just one piece of fabric covering them. It was heaven in my mouth, and heaven on my chest.
After we’ve played enough, she broke away, the drool from our kiss forming lines.
I was curious. “You like this?”
“I like it really, really. A lot.”
Well, I can see that. Her nipples were hard, and her (my) boxers were wet.
“We didn’t set a rule for your masturbation.”
“Let’s do the same thing. Oh, wear your new panties first.”
I put on her new panties, pink, this time, and put on my pants and got up. She took my place at the desk and took off her (my) boxers, and rubbed herself off using them. I sat on the other side watching her as she did so.
“Ah, maybe I should get some more boxers?”
“Y-yes. Be quick.”
I got back, having chosen a grey pair that were quite tight but comfortable. I wanna see the cameltoe~
She masturbated to an orgasm, almost as quick as mine, and she then threw the used, wet boxers in my face. I did as she had done and licked them and shared a kiss. She dressed up in her new boxers, still quite red.
“It’s so nice that we met, and had matching fetishes.”
“Yeah, must be Fate at work.”
“Hey, why do you think we have such matching fetishes? And such weird ones, too?”
“Well, who knows? Maybe they’re the fantasies of our creator and we’re just two characters in his wet daydream.”
They laughed and kissed, very sloppily. Another one of my fantasies, of course.