Alex knocked gently on his sisters door and waited but upon not receiving any response, slowly opened it.
The inside of Shana's room had many posters of famous heroes of the Realm Guard on the wall, embodying her desire to use her superstrength to become a hero just like them. There were newspaper articles and cutouts from Christmas Terror incident when a group of cultists managed to conduct a mass summoning of demons on the Christmas of UC 3280 that cost the lives of over 200,000 people but was finally stopped by the heroes of the former era.
In the corner of the room, there were a rack of extremely heavy weights and resistance ropes alongside boxing gloves that she used for combat training. It was all low level training equipment, but Shana had been using them for years and the wear and tear was apparent.
There was also a desk with a laptop on it and her school items, as well as a two-shelf bookshelf which had a collection of trophies from underage strength and martial arts competitions. Alex knew that even young, his stepsister had always had a brutish side to her.
A small scented candle was currently burning on the shelf, but it did little to mask the scent of Shana through the room.
At the other end of the room, was her bed that had a large lump under the covers.
"Shana?" Alex asked, poking the lump that was clearly the girl.
She didn't respond, but he knew she wasn't asleep given how that lump moved and curled up more from his touch. He tried to pull the covers back, but the girl held the duvet with a strength far surpassing his own leaving him helpless after several tries.
"Hey, stop being so stubborn!"
Still no response.
Changing tactics, Alex grabbed the duvet from the bottom of the bed and pulled it up, catching his sister by surprise and exposing her legs. He grabbed one of her legs and tried to pull her off the bed, but she stubbornly fought back and managed to kick him on the jaw with more strength than she intended to, knocking him over and hitting his head on the low hanging bookshelf on the way down.
[Sturdy as an M +565 exp]
"Ow!!" Alex cried out in genuine pain and clutched his head as his vision spun.
Several of the trophies were knocked over, and one of them even snapped in two.
"S-sorry!" Shana cried out in a panic, pulling the sheets down and sitting up with a look of worry.
"...Can you stop being so stubborn?" Alex asked while writing around in pain on the floor like a worm.
The sight was so ridiculous that Shana forgot she was upset for a moment, but soon asked nervously, "Is it... because of me?"
"What?"
"Are you going to move out because of what happened yesterday?!" Shana's face was bright red as she insinuated they're morning in the bed in which his hands roamed about her body lewdly.
The pain had subsided enough that Alex got off the ground and sat on the side of her bed, "No, not really. It's related, but different. I awoke a system"
As Alex looked at her disheveled appearance, his gaze homed in on her chest once again and grew lewd. Shana for the first time, ignored it as she had other worries on her mind.
[Lusty Gaze +17 exp]
"...And you have to leave because of that?"
"It's a lewd system."
"I-if that is all, it's fine. I will forget what happened yesterday, so please stay..."
"I will keep being lewd, I can't control it and if I want to get stronger, I have to do it."
"T-then, I will w-wake you up in the mornings..."
Shana's face and ears were bright red as she essentially offered her body to Alex to advance his system. Alex licked his lips slyly in response, causing the girl to flinch but she didn't rebut anything or complain.
"Thank you but... just that isn't enough for what I need."
"T-then..."
Alex moved over the bed and sat closer to her before hugging her. The blonde girl didn't resist and let him pull her against his chest, shutting her eyes deeply and inhaling in his scent.
"I'm sorry for being a creep, Shana."
"Y-you're not."
Alex released her from his hug and placed one hand on her cheek before pulling her closer and placing his lips over hers. Shana's body turned completely stiff as he kissed her, but she in no way rejected it.
He didn't stop at one kiss, but kissed her a second and third time. Shana was very rigid at first, but her lips soon loosened up and she even grabbed onto his shirt with both hands.
She was awkward, having never kissed anyone like this before, but did her best to match whatever Alex was doing so when he began to try invade her mouth with his tongue, she mirrored what he did.
Even the girl's tongue was enhanced by her superpower and Alex had no means of resisting when it fought back, but Shana seemed to be considerate and would retreat to let him win some battles.
Slowly, Alex pushed her onto her back on the bed and whispered in her ear, "Shana, I love you"
"G-good."
This was too much for her heart that was beating viciously in her chest and she become more frantic in her kisses.
Alex's hands roamed about and dexterously undid all the buttons on her shirt, exposing her wheat tanned skin underneath.
"No bra?" He commented slyly.
"I'm in pajamas, idiot."
Alex groped and squeezed without restraint, inwardly complimenting how a more modest chest could fit into the palm of his hand better than a larger one.
Shana began to reciprocate his intimacy, running her fingers through his hair while her kisses became more forceful.
His lips soon became an explorer of her body on a journey south. They explored all the peaks and ravines on the way down, leaving no territory uncharted while drinking from the salty waters of the earth to sustain himself.
He passed numerous tribulations before finally ventured into the marsh, the earth here somewhat paler compared to the earthy wheat color of the prior lands.
The explorer tasted the waters of the marsh to assess the safety and it seemed to be fresh, indicating the ground was still soft. The low shrubbery scratched at his ankles as he explored this region but the most dangerous experience was when he fell into a sinkhole, the muddy ground around his body so hot it felt scorching on his skin. He attempted numerous times to extricate his body, but it kept getting pulled back in.
Shana's chest heaved up and down and her fingers curled from the pleasure. She emitted muffled, high pitched whines from her pillow as she struggled to restrain her voice.
Her hand grabbed onto Alex's head while being careful not to hurt him, but it was an active endeavor that became harder and harder to more ragged her breath became.
Eventually, after a final lengthy whine, the sinkhole entrapped the explorer along as a geyser of hot water shot out from below.
"Haah.... Haaah... tell me... you love me..." Shana whispered in between panting with her flushed cheeks, pulling his head back up to her chest before her arms and legs latched onto him.
"I love you," Alex stated, even if perversely, resulting in her grip on him strengthening.
"M-more."
"I love you."
"More."
"I love you."
Shana peeked out from below the pillow and revealed a heavy blush, her ears almost completely red. She suddenly over so Alex was on the bottom and pulled the duvet up.
He couldn't see, but the blanked rustled and bobbed up and down as Shana yanked down his pants and decided to reciprocate.
It was intense, Alex only able to feel her damp, hot breath while the constriction was arguably too strong. Still, he enjoyed the experience of her doing her best, even if she struggled to fully engulf him.
Despite the inexperience, he felt the the pressure gauge continuously climbing and held her head as he guided her to address the pipe in question.
Just as he was about to warn her of an imminent failure of the pipe, there was a sudden knock on the door followed by their mother's voice, "You two, dinner is ready so come down and eat."
Shana was even more frightened than Alex, unaware that her mother had implicitly told Alex she approves of their relationship. The suddenness of the voice caused her to slip and swallow the outlet of the dangerous pipe.
Alex, his pressure gauge already in the red zone, felt the sudden wrench and curled his toes as the pipe burst and poured the pressurized water directly down the new found exit tunnel.
Shana was shocked and felt the pipe burst down her throat, but with his hands pressing on her head tighter than ever, bore through the deep discomfort and drained what was left in the pipe before separating herself from the ironworks.
"W-we'll be right there!" Shana called out in a panic as she emerged from the covers lying atop Alex, wanting to prevent her mother from coming in.
"Alright, hurry up," Mrs. Ivanov chuckled before Alex heard the sound of her footsteps leaving.
Feeling relief, Shana looked at Alex and kissed him, her original hesitation no longer seen.
"...That..."
"That?"
"I will do that for you every morning, so you aren't allowed to leave, okay?"
Shana's cheeks were flushed red while the feeling of an object stuck in her throat remained prominent. His system had also come out with the final points as well.
[Sin Points +152]
"...I am still leaving."
As if thinking about something she should have questioned before, she asked, "Where will you even go?"
"..."
His lack of an answer was enough for Shana to get a clue. His system was all about sex, and he was leaving because of it, meaning there was probably another woman.
"...Step brother, who is it?"
"A classmate."
"A male classmate?"
"..."
[Sturdy as an M +215 exp]
Alex felt like he was going to throw up his lunch as Shana's fist hit him in the stomach. She was lenient though, the system points showing it was much gentler than earlier.
"Idiot, bastard, sex fiend, scumbag..."
Shana started to tear up and buried her face in his shoulder while calling him all kinds of derogatory names.
"I love you."
"Liar."
"I do."
"Then be with just me."
"..."
"...Liar."
There was nothing Alex could do other than hold and try to coax her.
"You have always wanted to be a hero, and I am a big villain."
"Then I will lock you up so you can't hurt anyone."
Alex chuckled and quipped, "Hey, careful there, you are going down the crazy route."
"I want to meet her."
"That's fine, I plan to ask her to help me move."
"Good," The girl stated while wondering if she should move out with him instead.
Shana then climbed out of the bed and begun searching for her underwear and pajama pants that Alex had thrown aside earlier.
"Hurry up, dinner is ready," She stated to Alex who was still lying in her bed as if it were his own.
"I know, I just want to look a bit longer."
Shana blushed but she turned to face him wearing nothing but an unbuttoned pajama shirt and put her hands on her hips. She was completely exposed but could only hold back her instincts for half a minute.
"T-there, I will let you look more later, now get up."