Roberto Santiago was fighting to keep his eyelids from drooping and losing. He reached under the desk and pinched his leg through his jeans, but all that did was making him sleepy and hurty.

At the front of the room, Mrs. Robertson stood before a whiteboard and attempted to coax the class through a particularly difficult equation. She had a voice like a beehive. Droning. That didn't help matters. Bobby blinked and crossed his arms. Alright, man, focus, you can not afford to flunk this class. His lids were sooo heavy, though. How about this: I'll close my eyes, but keep my ears and brain open. Yeah. Okay. He closed his eyes, and before he knew it Mrs. Robertson was shaking him awake. "If you'd like to nap, Mr. Santiago, there's a very comfortable couch in Principal Everline's office."

The entire class laughed at him, and he felt an inch tall. "Sorry, Mrs. Roberson," he said and smiled sheepishly. "Won't happen again."

"Good."

She went back in front of the class and somehow he made it through the rest of the period without falling asleep. His next class was study hall, then, home. As he tried to focus on his homework, his mind drifted. He couldn't do this much longer. Sure, he had a responsibility, but this staying up all night shit was really affecting him. How could he break it to her, though?

At the end of the day, he grabbed his books from his locker, shoved them into his backpack, and then went home, his shoulders slumped and his mind fuzzy. At several points he thought he was literally going to fall face-first against the sidewalk...if he did, he wouldn't be getting up anytime soon.

When he got home, he hung his bag from the hook behind the door and tried to sneak into his room for some shut eye, but Ronnie Anne's voice drifted into the hall. "Hey, Bobby, that you?"

His shoulders slumped. "Yes, it's me," he sighed.

"Good. Come here."

Great. Just perfect. There goes my nap.

But he was a good brother and his sister needed him. In her room, he found her leaning back on her bed, naked save for a pair of purple socks pulled up to her knees. Her hair was held up in a ponytail. Her legs were spread, revealing her pink, glistening sex, and her tiny nipples were rock hard. She grinned at him with half-lidded eyes. "Hey."

"Hi," he said flatly, his hands working at his belt automatically. He unbuckled it, and his pants dropped to his ankles. Ronnie Anne watched him with lust-filled eyes, a seductive smile playing across her lips.

Bobby stepped out of his pants and then slid his boxers down, his flaccid penis flopping limply out and lying against his sack. Ronnie Anne's tongue darted out and swiped across her bottom lip, putting him in mind of a reptile.

Naked from the waist down, Bobby grabbed his penis and tugged on it until it was semi hard, then he went to his sister. She lifted one leg with a playful grin and he hooked his arm around it, the head of his dick poking her leaking hole.

He closed his eyes and swallowed, his Adam's apple bobbing. Like he did every time he had sex with Ronnie Anne, he thought of Lori. When he was hard enough, he thrusted into his sister; her wet, silky insides formed around him and he had to pretend extra hard that he was doing his girlfriend and not his sister.

Ronnie Anne didn't last long – she never did during their after school tryst. Eight hours of building pressure makes a girl cum very quickly, apparently; Bobby thought that only happened to dudes. When he felt his own climax forming, he pulled out and finished himself: His cum splattered Ronnie Anne's face and breasts. He didn't look, but he knew her mouth was wide open and her tongue stuck out, desperate to catch a drop.

Done, he turned, grabbed his pants and underwear, and left without a word.

In his room, he laid back on his bed and put his hands behind his head. When your sister's a raging nymphomaniac and not getting laid every couple hours makes her depressed and physically hurts her, what's a good brother to do?

If only she wouldn't keep him up half the night...