Supervillain Idol System: My Sidekick Is A Yandere

Before Don or Sylvia could say anything, Summer expressed her shock in whispered tone of surprise. "Sylvia what the hell!?"

Sylvia turned to face her surprised best friend for a moment but put on a cute face as if what she had offered to do wasn't incredibly absurd. "What?" she asked innocently, "I'm just trying to make up for it since it's my fault. I'm sure your 'big~' brother agrees."

As she said this, she brought one hand to Don's crotch and casually rested her palm against his bulge, feeling it out slightly as she spoke.

Don could never have predicted the situation escalating to such a point so quick so he was at a loss for what to say. On one hand it was a very tempting offer but on the other he wondered if it would negatively impact his relationship with Summer.

Before he could reach a conclusion, Sylvia began to progress on her own, not even waiting for Don to consent to the offer. She quickly went from merely resting her hand against his bulge to holding the edge of his boxers, which she began to slowly slide off.

Summer's eyes widened as she saw this and her cheeks turned beet red. She was not only flustered, but completely flabbergasted at what she was seeing. She then found herself raising her head to look at Don but upon seeing that he wasn't against what Sylvia was doing, she frowned.

"Are you just gonna agree to that!? What the hell??" She asked, occasionally stealing glances at Don's crotch as she did so.

Don didn't really know what to say in response so he could only shrug and pass the blame elsewhere, after all, it's wasn't as if it was his idea. "What? She's your friend and you're the ones who decided to break in here."

Summer felt a bit embarrassed by Don's reply as she couldn't really argue with his point. But when was that ever an issue for girls in arguments?

However, before she could say any nonsense in defense, Sylvia finally lowered Don's boxers enough to allow his cock to pop out into the open, fully erect and hard.

"!!"

Both Sylvia and Summer expressed surprise at the sight to a varying degree. Sylvia looked more excited whereas Summer seemed even more shocked.

'That's his cock? Why's it so fucking huge?' Summer thought while staring at Don's cock with wide eyes. As if the sight of it alone weren't enough, an eager Sylvia leaned slightly forward more and used both her hands to hold Don's cock by the shaft. "*Mmm~* Well hello you~"

Sylvia looked up at Don while maintaining an innocent face. She gave him a small smile and began to gently move her hands up and down in slow gentle motions, stroking his cock. "Well?" she asked in a teasing tone, "you still haven't told me whether we have a deal or not?"

Almost immediately Sylvia asked this, Summer raised her head to look up at Don with expectant eyes. Don glanced at her in the corner of his eye and thought himself, 'well, no risk no reward.'

He then glanced down at Sylvia and replied, "Well, since you offered, it would be rude of me to say no."

Sylvia smiled mischievously at the answer and tightened her grip around Don's cock before replying, "*mm~* true, it'd be such a shame if my best friend got in trouble because of naughty little me~"

Just as she replied, Sylvia leaned closer to Don and opened her mouth before wrapping it around the tip of his cock. *mm~*

Summer was in disbelief and quickly looked away to face the wall. "That's so fucking gross Sylvia!" she muttered in a low annoyed tone.

Sylvia looked her way in the corner of her eye and tried to reply while sucking on the tip of Don's cock. "Itsh~ not sho bad Shummer *mm~* shee?"

Summer couldn't help but look Sylvia's way out of curiosity. The sight of her best friend stroking and sucking on her brother's cock left her feeling very strange. It was an emotion she couldn't express in words.

She remained quiet but her gaze remained fixated on Sylvia as she continued to pleasure Don.

Don also saw this in the corner of his eye and thought, 'wow, she's really watching. Maybe she's more interested than she lets on.' Though a possibility, Don felt it was too risky putting it to the test.

The best he could do was observe her and her reactions to gain some takeaways from all this. With that in mind, he decided to take a slightly more active role and brought one of his hands forward to hold Sylvia by her head.

"*Mmm~*" She let out a soft moan and rolled her eyes to look up at him in a seductive way. Don met her gaze as he began to guide her movements.

With Don helping with that aspect, she kept her focus on twirling her tongue around his tip as she sucked and slurped on it. *slrrp~* *plop~* *mn~*

Sylvia began to moan more and more softly, her sweet cute voice causing Don to feel his cock get even harder.

Don quickly found himself wanting to feel more of Sylvia's mouth around his cock so he no longer held her by the head gently but began to use slightly more force to bring her head toward him.

Sylvia quickly understood what Don was trying to do and so she moved both her hands from his shaft and allowed him to bury his cock deeper into her mouth. *glawk~* *glawk~*

However, much to Don's surprise, she had trouble just taking even half of his cock into her mouth, even going as far as to accidentally brush her teeth against his shaft. Don stopped moving her head once she did that and he looked at her with a bit of confusion.

Despite her earlier eagerness it now became clear to Don that she wasn't at all good at this. Sylvia, however, didn't seem the least bit dissuaded as she proceeded to hold his shaft with both her hands again before leaning forward and allowing the warm meatiness of his cock to brush brush against her face as she said, "*whoopsie~* Sorry about that, it's my first time trying out a real cock.

It's nothing like my toys but don't worry, I'm a quick learner."

She winked at Don before pulling his cock away from her face and opening her mouth again. This time before directly taking it in, she used her tongue to lick it from all sides, slowly running her tongue from below the base of his balls to the top of his cock, where she proceeded to open her mouth and take in his tip once again.

She paused for a moment there and began to use one hand to vigorously stroke his cock while passionately sucking on the tip. *slrpp~* *glurk~*

Summer's face was now completely red but oddly enough she was still watching the scene quite intently, though, her expression of surprise didn't fade in the least.

'Fuck, why does this look so hot? This is so wrong.' Summer thought to herself as she brought her legs closer together, finding herself feeling tingly in her lower areas the longer she watched this.

At this time, Don wasn't glancing her way and so these subtle shifts in her posture went unnoticed. 'Wow, her hands are really soft, and her mouth….' Although it was plainly clear that Sylvia wasn't as good as someone like Trixie at doing this, Don found that she had her own unique sensation to give which brought him incredible pleasure.

He groaned out as he felt Sylvia's mouth get even wetter, with her tongue constantly being twirled around the tip of his cock. Summer couldn't help but slightly bite her lip as she saw this, causing her to bring her legs even closer together. 'Fuck! why am I getting turned on by this?' she thought, feeling very confused about what she was feeling.

Meanwhile, as good as the current fellatio from Sylvia was feeling, Don still wanted to bury his cock a little deeper. So once again. He held her head more firmly and thrust his hips forward *Glurgk!~* Sylvia's eyes widened as she suddenly went from only sucking his tip to feeling a large part of his cock stuffed in her mouth.

She instinctively placed her hands on Don's hips, trying to pull her head a little bit away so she could breath and recompose herself. However, Don's grip was firm and he didn't allow her yo move away, keeping her head in place as he began to thrust his hips forward and back.

*Glrugk~* *gawk~* Sylvia's eyes became watery and remained wide as she looked up at Don in surprise while he pounded her mouth with his cock, though still not fully thrusting it in.

Don would occasionally feel some of her teeth, but with a body as durable as his it was more of a lighter irritation than anything else. And so he didn't overly mind it. And for Sylvia, her attempts to back away were quickly replaced by muffled moaning that began to resonate in the entire fitting room. *Mmph~* *uh~*

'Fuck. Why does this feel so amazing. My whole body is getting hot,' Sylvia thought. She found a strange pleasure in having her mouth used this way, a very different experience from toys.

Summer even began to rub her legs slightly together as she felt the subtle moistness on her own panties, which left her feeling both ashamed and embarrassed. However she was unable to look away.

The entire situation was incredibly sensual and so Don found himself quickly reaching his limit. "Fuck…" he muttered before giving one final thrust while still holding Sylvia's head in place as he reached his climax, blowing his load into her mouth.

As Don's cock began to throb, Sylvia panicked slightly and pulled her head away, causing his cock to pop out of her mouth just as he climaxed. This caused him to shoot some of his cum onto Sylvia's face, with a little landing on Summer's cheek.

Summer's eyes immediately widened and she was about to say something but then they could all hear footsteps outside the fitting room before the store clerk's familiar voice asked from outside, "Is everything okay?"

Sylvia and Summer both showed panicked expressions while Donn couldn't be fazed by just this and so he managed to form a quick reply saying, "yeah I just accidentally snagged a bit of my skin while trying to zip on some pants. Uh, have the two girls I was with come back yet?"

"Oh I didn't see them go out. Maybe there in the restroom. Do you need me to go get them for you?" The store clerk offered.

"I would appreciate that."

"No problem." The store clerk replied and in the next moment, they could hear her footsteps as she walked away.

Summer, whose heart was now beating incredibly fast, couldn't help but let out a sigh of relief. Whereas Sylvia used one finger to trace the cum off face before looking up at Don and saying, "I hope you keep your end of the deal."