And why would it do that?

Even if the last thing you ought to be doing is "buying" scandalous underwear for your own sister, you have to admit that the spring it puts in her step is a small reward for you. Sure, she's probably just patting herself on the back for hooking you around her little finger, but happiness is happiness, right? Making other people happy makes you happy, which is... probably why it's so easy for people like Theresa to take advantage of you.

Oh, well. What's the worst that could happen?

With some daylight left, Theresa finally makes good on the promise of getting you to the gym. You're more eager to get there than you might have expected to be, but not for any reasons you could have predicted. Shopping with your sister has put undue strain on your sanity, and a chance to work off some physical energy would be a welcome distraction from the delinquent thoughts invading your mind. Aching muscles and burning lungs should do the trick; anything to stop seeing her in nothing but strings and tissue paper undies.

As the two of you stride into the gaudily painted facility, you immediately split off to get changed in the locker rooms. Cold and isolated, you take relief in this brief respite, unbuttoning your shirt while no one else is around to take notice.

But, then again... what would they take notice of? There's really nothing noteworthy about you. The shirt comes away and you see the same milk toast torso you've always seen. No muscles to speak of, but no excess body fat either... you could be used as a model for "Default Human," dull to the point of invisibility. You'd always told yourself that being average was okay, and that was sufficient any time you caught yourself in the mirror. Or, it would be, if you were average. Sitting in a gym bathroom, you let it sink in that you're not average. You're boring. With a bit of effort, you might be able to work up to average.

A loud clatter of a nearby stall door jars you back into reality and you quickly resume changing clothes. Self-deprecating introspection isn't going to build any muscles! That's the whole point of going to the gym, right? It's the first step in trying to be a little less boring, a little more like somebody you can acknowledge properly. A better you!

Once changed into your new, surprisingly comfortable workout attire, you step back out onto the floor and scan along to see where your sister has planted herself. You quickly spot her on some of the large floor mats off to the side, warming up with some stretches. What were long strides in her direction at first dwindle into a foot-dragging crawl as you get a proper look at Theresa in the outfit you'd just claimed for her. God. Damnit.

She may as well be in underwear, for all that's covered by her skimpy attire. That colorful sports bra and shorts may as well be painted on, snugly gripping her curves in all the right-wrong ways. Her eyes meet yours as you barely approach, open mouth curling into a grin as she waves you closer, still reaching for her toes stuck out in front of her.

"Hey, c'mere and give me a hand! I can aaaaaalmost... reach! Push on my back a little bit, see if I can get there, and then we'll get you started, okay?"

A simple enough request, you wager. Gulping down your shame and indignation, You crouch down behind your sister, fretfully placing your open palms against her shoulder blades. Having little **** of your own to speak of, you give her a measured bit of pressure, feeling her muscles tighten beneath your fingers. Folded in half like that, Theresa's breaths were quick and shallow, grunting softly as she tried getting just a little farther.

"Not too hard, not too hard... mngh!" Your brain knew that the noises she's making are those of strain and effort, not of pleasure... but your dick didn't really care. Your face lit up, hands pulling back as you step away from your shameless sister. Disappointed, she relaxed her stretch and pouted back at you, looking over her shoulder. "Aww... I was almost there, I could feel it! Way to leave a girl hanging, Bubby."

A response tries to burble out of your mouth, but you're not sure what language it was keyed to. Her pout quickly shifts back into a grin as she springs onto her feet, patting you on the shoulder. "Alright, noodle man, your turn! Let's get you limbered up and on those weights!"

"Weights? Can't I just use the treadmill?"

She scoffs. "What good is that going to do? You already jog every morning, doofus! You're not gonna get buff if you just keep doing that."

"Sis, I don't want to get buff," you complain. "I'm only doing this because I kinda already roped myself into it."

"Well... alright, maybe not _buuuff _buff, but you oughta put on a little bit of muscle! You'll feel good about it, and it'll boost your confidence!" She poked your chest, boring those glittery eyes of hers right into you. "If nothing else, do it for Peeeenny. You wanna look nice for her, don't you? You keep looking her way, give her something to look back at. Boys aren't the only ones who like to ogle."

As if giving you a demonstration, Theresa's eyes scanned down your front and back up at you, bouncing her eyebrows playfully while giving her lower lip a hungry nibble. The gesture alone was enough to set your face alight again, eliciting a giggle from her. Was this motivation or just more teasing? Only someone like your sister could find a way to blend the two and still get results.

"Alright, fine, fine! You're the expert here, so I'll... follow your lead." Muttering, you weakly add, "...For Penny."

Dear merciful heaven above, how many hours have you been lugging around these useless hunks of iron? Three? Five? Your arms burn, your back aches, your legs have become jelly, and your lungs are suing you for custody of more air. Flopped onto the floor mats, you shakily reach for your phone, checking the time to see that it has been exactly...

Seventy-five minutes. A sweaty mess, you would welcome the sweet release of **** at this point. Theresa looks fairly winded as well, but her healthy glow and peppy demeanor take the fatigue in far greater stride than you possibly could. Sis is right, you are definitely a hopeless noodle man.

On the bright side, your searing discomfort has done the job of keeping your cock in check, with blood having far more important places to be than stiffening your sausage. Good thing too, because Theresa has been the most deliciously insufferable tease the entire time. Every bend, grunt, and sigh has been pointed right at you as she exercises nearby, giving you shameless visual access to her toned, round ass and straining bust, both barely covered by her skimpy workout attire. With eyes closed, even her breathy words of encouragement could be construed as bedroom talk, making either option a hopeless choice for you. Thankfully your body can go through lifting motions even if your imagination is paralyzed by invasive thoughts of pouncing atop Theresa like a wild animal. If you didn't know better, you would swear that she's doing it on purpose.

You're not the only one who's noticed, either. While you're backhandedly thankful that Theresa's display has kept you from focusing on all the other men in the gym, green-eyed for their machismo, you'd be blind not to see their stares lingering on your sister's alluring curves and positions. You spot one pat the other on the shoulder, pointing her way and giving his friend a cocky, approving grin. You're not sure how Tess feels about being ogled, her focus entirely on you and your scathing workout routine, but given her outgoing demeanor, you would guess that she likes the attention. She's had more than enough boyfriends to convince you that she doesn't often shy away from men's advances.

Not your problem. Theresa can do what (and who) she wants; none of your business. Barely able to lift your own limbs off the floor, you drag yourself to your feet and let her know you're going to go clean up and change back into your normal clothes. She gives you a thumbs up while taking a long draw from a water bottle, practically posing like some bimbo on a fitness magazine. Yeah, she's an attention whore alright. Rolling your eyes, you leave her to her horny man-fans.

~

A quick, cold rinse of a shower and some fresh clothes later, you're ready to meet back up with Theresa. What you find, however, brings the hairs on your neck to a bristle. Theresa is having what appears to be chatting with one of the guys who had been making eyes at her, but that isn't the part that surprises you. What stirs in your gut is that Theresa looks a little uncomfortable. She's back in her jeans and crop top, so it looks like he slipped up to her the moment she got out of the locker room.

"Alright, here, look!" You hear her half shout as you get within earshot, pointing in frustration at your name across her arm. "I belong to him, see? It wouldn't work, anyway."

The burly guy curls his nose at the information presented to him, giving her a dismissive shrug. You can tell getting closer that he's a little old to be flirting with a college student, but has that older rugged charm that might still do the trick. "Yeah, so? Not a deal-breaker, is it? He's your owner, not your boyfriend. I'm sure he won't mind if you ask him nicely."

Her eyes meet yours, flicking back up to Mr. Scruffy Stubble. "Why don't you ask him yourself?" Once the guy starts to turn your way, you catch Theresa making a swiping motion across her neck, jaw clenched in disapproval. Makes it pretty obvious she's not interested, but also isn't making a big scene.

Now face to face with the guy yourself, though, you can feel your throat clenching shut, fresh beads of sweat dappling your brow. Beating you in several inches of height and width, it takes a lot of willpower for you to keep your back straight and eyes from looking at the floor.

"Hey, pal," he starts on you. "You're her owner, yeah? What's a guy gotta do to, y'know, borrow her for a few minutes?" His smirk is friendlier than you expect it to be, but the notion that he's basically asking to rent your sister puts a sour taste in your mouth. Did other people also look at her as property because you'd claimed her? This wasn't really a facet of your power that you particularly enjoy.

"Look..." you swallow hard, trying to get your thumping heart to ease off a bit. "Yeah, she's mine. She's also my sister, and still a person, so if it's come to the point where you're asking permission, I don't think she's interested." Your voice is riding a razor's edge, balancing between fear and aggression. Showing either one could turn this whole thing sour, and the last thing you needed was any more pain wracking your body. Catching hopeful glances from Theresa did put some steel in your spine, though.

Much to your very thankful surprise, the big guy calmly put his hands up in surrender, eyes closed with a grin. "Fair enough, man, I was just checkin'. You take good care of her, yeah?" He pats you a little too hard on the shoulder, chuckling as he starts to walk away. "It's no good to leave her all wound up."

...And that was that. Immediately feeling stupid for blowing the whole thing out of proportion in your mind, you heave a held sigh and give Theresa a puzzled look. What did that guy mean about her being "wound up"? It's her turn to glow like a light bulb, her knees rubbing together awkwardly as she struggles to look you in the eye for a second.

"Thanks Bubby," she murmured, smiling softly. "I could have handled it myself, but it felt nice to have you on my side, too."

"He didn't try anything with you, did he?"

Her little smile is tinged with... pity? Honestly, what would you have even done had the guy not been so passive about things? "No, nothing like that, just... asking questions, making assumptions. It's fine, don't worry about it. Let's just go, okay? Are you ready?" You nod, body automatically following along with your sister while your thoughts started to pull apart what had just happened.

Is that normal, for things to dissolve so abruptly? It felt rushed, almost ****, the way he suddenly just gave up and went on his way. What exactly happened before you caught wind of it? You still don't know what he meant before, but seeing your sister uncomfortable was reason enough to let it be. Problem resolved, you're moving away from the stress and heading back to the car. Maybe it's better to just let it go and not dwell on it.

Theresa is quiet on the way back home, stowing away her teasing quips and jabbing small talk for a little while. Her strange behavior reinforces the feeling that things aren't entirely okay; that something's going on under your radar. Did you do something wrong? She'd probably tell you if you did.

Letting your body relax in the car reminds you of how hopelessly sore your entire body is. Whatever's going on, it can wait for a time that you're better equipped to handle it. All you want to do is go home, not move, and call this bizarre day over with.