My little sister wanted to lose some weight, but dad kept making her high-calorie breakfasts in the morning, complete with bacon, sausages, eggs, pancakes, and yogurt. She didn’t want to hurt his feelings by not finishing her food every morning, which meant the only alternative was to skip breakfast altogether. Needless to say, she always complained to me of being tired during the day when she went to her catholic school.
This morning, she came to my room dressed in her school uniform, asking for a favour.
"Monica told me yesterday that she always feels really energetic the morning after her boyfriend cums inside of her. She says there are some nutrients in semen that gives her enough energy the next day. You know how I don’t eat breakfast anymore since dad’s breakfasts are making me gain weight, but I can’t stand being so tired all the time at school… will you help me?"
I couldn’t reject my innocent little catholic schoolgirl sister dressed in her short plaid skirt and fitted white blouse, so I positioned her on my bed and lifted her skirt over her butt. I pulled her innocent white panties down, revealing the beautiful treasure it concealed… my cock sprung to attention. I didn’t hesitate to push it into her warm, tight little pussy.
"Ungh, hurry up big bro, I need to leave for school soon…" I started to pound her quickly, eliciting a satisfied moan from my little sis. I suspected she was enjoying this too, but I was too focused on my task to pay more attention. As I pounded her hard, I whispered that I was going to cum, while feeling her starting to tense up. "Wait, bro, just keep going a little longer… !" she moaned.
I couldn’t hold on anymore. I plowed into her as I prepared for my release, and just as I reached my plateau, my little sister gasped, “Ahhhh bro I’m going to — !”
I pushed into her one last time, pressing my balls against her clit as I pumped my load into her tight, convulsing pussy. I was having trouble holding on as my sister’s legs spasmed in pleasure. She dug her face into the bedsheets as she tried to suppress her voice, but she couldn’t help but let out a small yelp as she orgasmed intensely.
I pulled my cock out of her and watched her tight pussy squeeze a little of my warm cum out. She laid there in the same position, panting heavily. “Thanks, bro… I think that’s enough energy to last me until the end of the day.” She pulled up her white panties over her cum-soaked pussy, slowly got up and walked back to her room.
As soon as she got home from school that afternoon, I heard footsteps and then a knock on my bedroom door. “Thanks again for this morning, big bro. Monica was right, it does feel amazing after being filled up with cum! I didn’t feel tired at all today, and it’s all thanks to you!” She hugged me, probably relieved that she had finally found a solution to her problem.
"I just need another favour, big bro. I’m starting to feel a little tired, and I have a soccer match tonight… would you mind helping me out again? I need to be on the top of my game tonight."
I couldn’t refuse. After I pumped another big load into her from behind on my bed, she thanked me and promptly got dressed for her game. They beat the other team 2-0, and my sister scored both of the goals. After that, she became a thorough believer in the power of my semen, coming to my room twice a day to collect my cum in her pussy… even after she missed her period and started mysteriously gaining weight again.