Arachne(CYOA)

"Hey, son, I'd like you to meet your new mother and sister!"

 

At first, you thought that your father had finally lost his mind. Marrying a monstergirl? In today's society? But, after seeing how happy they were together, you realized that, for once, your father had found someone that genuinely loved him.

 

However, getting used to having new family is difficult. Your new sister is constantly bullied for her abnormal appearance, and as her stepbrother, you have to stand up for her, even if it means losing all of your friends.

 

One night, you hear someone knock on your door.

 

"Brother, are you awake?"

 

You answer your sister's call.

 

"Can I come in?"

 

You invite her into your room. Opening the door, she crawls inside, dressed in her specially-made footie pajamas. She stands at your bedside.

 

"Brother, I need to sleep with you tonight."

 

Oh boy, here we go again.

 

Your sister is prone to feeling lonely and isolated, and can be a tad clingy. It was cute at first, but now it's become a nuisance.

 

You wouldn't have a problem with sharing the bed if her abdomen and legs weren't so massive.

 

However, you give her your consent, for the sake of maintaining your honor as a brother.

 

"T-thanks."

 

When you wake up, you're almost late for class, and she's still snoozing.

 

She's a heavy sleeper, it'll take some time to wake her up.

 

You decide to wake up your sister, and be late for school. Nobody likes you there, anyways.

 

After shaking her for about a minute she finally wakes up.

 

"Uwww... Good morning, Brother. Huh? Tardy?"

 

Your sister frowns. "Brother, I don't I wanna go to school. They don't want me there."

 

You do your best to explain the importance of a high school education.

 

"I don't care! I don't want to be around those people anymore!"

 

You threaten to leave without her if she continues to complain.

 

"As if! You're just as lonely as I am."

 

You decide to stay at home; it's not like you'll get in trouble, your parents couldn't care less.

 

You play games with your sister to pass the time.

 

The doorbell rings. You answer the door.

 

Standing before you is a vividly blushing brunette, holding a set of papers.

 

"I-I know that people don't like you... b-but I appreciate what you're d-doing for society! A-anyway, I just wanted to check up on you and your sister. I brought today's notes and homework so we can study together! May I come inside?"

 

You invite her inside, and call your sister down.

 

"B-brother? Who is this?"

 

You explain the situation to your sister.

 

"Is that so? Well, if brother says so, it must be the truth."

 

You study for what seems like an eternity. Eventually, the brunette decides to leave.

 

"Well, this was fun! We should do this again sometime!"

 

...

 

It's late at night, and your sister wakes you up from a pleasant dream with a thunderous knock on your door.

 

"H-hey, brother? Can I come in?"

 

You give your sister permission to come in.

 

"Thanks, Brother."

 

Instead of asking beforehand, she immediately climbs into your bed, wrapping her chitin-coated legs tightly around your body.

 

"Hey, Brother, who was that girl? Do you know her?"

 

You tell her that you've never met the girl before in your life.

 

"Oh really? Then how come she blushed whenever you spoke to her?"

 

You tell her that you're being absolutely honest.

 

"I guess I just have to trust you, huh?" She loosens her grip, and falls asleep.

 

The next morning, your sister refuses to go to school.

 

You decide to stay with your sister.

 

You play games in your room to pass the time.

 

The doorbell rings.

 

Before you can answer it, your sister wraps her arms around you from behind, and refuses to let go.

 

"Don't answer it! It could be an evil person!"

 

You try to break free, but it's useless. An arachne's strength is far greater than a human's.

 

"Stop struggling, brother! I'm trying to protect you!"

 

The doorbell rings again.

 

"Wow, they're really persistent."

 

Using her web, she sticks you to a wall.

 

"Stay right there, I'll get it."

 

She crawls toward the door, and answers it.

 

"Oh, hi!"

 

...

 

"He's really sick, I'm afraid he can't see anybody today. I'm sorry."

 

...

 

"Don't worry, I'll take care of him!

 

The door closes. Your sister returns.

 

"It was that girl again... she's really persistent. Hehe... Hey Brother, you look so vulnerable like this-"

 

The doorbell rings again.

 

"Oh, who could it be now?!"

 

As your sister descends the stairs, the window across from you breaks. Quickly, the brunette from yesterday climbs inside, and locks the door.

 

"Don't panic, I'm here to rescue you."

 

You hear your sister rapidly climbing back up the stairs.

 

Concerned about her safety, you tell her to promptly evacuate the premises.

 

She nods, and gives you a kiss on the cheek. "Good luck."

 

By the time your sister busts through the door, the brunette could've easily made it home.

 

"Nobody was at the door, I guess it was just a prankster! Ehehe~"

 

She leans against your body, pressing her breasts against you. "Now, where were we?"

 

She begins to rub her slender hand against the crotch of your trousers, but stops abruptly, sniffing the air.

 

She glares at you.

 

"Why do you smell like that brunette?"

 

You remain silent.

 

She looks around the room for a trace of the brunette.

 

"Hey, did she break this window? That's how she got to you, right? I bet she was planning on doing some horrible things to you... Maybe something like this?"

 

In the midst of being molested by your sister, the brunette silently climbs back through the window, and charges toward your sister! Leaping gracefully into the air, she delivers a swift kick to the back of your sister's head, knocking her out instantaneously.

 

The brunette takes out a bottle of clear liquid, and applies drops of it to certain areas of the web. The liquid fizzles, easily eating through the  web.

 

Free at last, you follow the brunette outside of the house.

 

"Come on, we can hide at my place."

 

You're still not sure if you can trust her.

 

Foolishly loyal to your duties as a brother, you re-enter the house. The brunette stares at you, confused.

 

As you enter the house, the door slams shut behind you. You turn around to see that it's completely covered in webs.

 

"So, you came back to you sister!" A voice chimes in from behind. "I'm so happy..."

 

She hugs you from behind, resting her head on your shoulder.

 

"So, do you wanna continue where we left off?" She whispers.

 

With her arms wrapped around your waist, she unbuttons and unzips your pants.

 

"I wonder what you think I'm going to do to you, Brother~."

 

She slides her hands under your shirt, and feels up your chest. Gently, she pulls your shirt off.

 

While nibbling on your ear, she slowly removes your pants, revealing your throbbing erection.

 

"Oh my, it's so stiff! You weren't actually thinking about fucking your sister, were you?"

 

She spins you around, and pins you to the ground, belly-up.

 

"Well, I want to let you in on a little secret."

 

She leans in close. "Your sister all that innocent, either."

 

Giggling, she readies the tip of your cock near her entrance, and slowly slides down.

 

"Aa~hn! Look, Brother! We're finally one! I'm going to start moving now, okay? Don't break~!"

 

Gingerly, she begins to raise and lower her hips. There's something about the warmth, the texture that makes her insides so inviting. You are tempted to push yourself all the way inside, and just leave it inside for hours on end.

 

"Brother, your tongue's hanging out. Does it feel good? I'm feeling good too..." Your mind, sugar-coated with pleasure, begins to drown her voice out.

 

You can feel your groin conducting some of the heat from her pussy, it feels almost like you're melting inside of her.

 

You are snapped out of your trance by an abrupt pain in your shoulder; unable to hold back, your sister has lodged her canines inside of your flesh.

 

"Bwuffer, Ih feews sho gooood!" She moans, slamming her abdomen against your pelvis.

 

It doesn't take long until you are brought to your limit, and you fill her twitching womb with your seed.

 

She keeps you inside of her, and you remain like this for the rest of the night. Of course, she would treat the bite wounds with her tongue later on, apologizing profusely.