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"You're such a good girl, you know that?" Nagatoro's eyes sparkled at her sister's words, letting out a pleased whimper in response. Her sister's dick pounded in and out of her pussy, hitting every sensitive spot inside her and making Nagatoro scream in pleasure on every thrust.
The lewd yet loving smile Nagatoro received from her sister made her arousal burn and her heart swell with love, only strengthened by the words that followed. "I can't believe my baby sister wants me to get her pregnant. I mean, I've always wanted to, I just figured you'd want Gamo or one of your other girlfriends to do it."
Nagatoro had to put forth all her energy to speak properly, her mind focused only on the heavenly pleasure she was getting thanks to her sister's dick. "I l-love them a lot too, but you were my first. It's only n-natural that my big sis pump a baby in me." Nagatoro husked out, every word punctuated with a whorish moan as her sister's cock kept thrusting into her depths.
"Aw, how sweet." Her sister said, her naturally teasing tone still managing to portray her sincerity. "In that case, let's make a baby, sis." With that Nagatoro's sister rammed her cock as deep inside her as she could. Nagatoro could swear her tip was pressing against her womb, the very thought of such a thing sending zaps of ecstasy through Nagatoro's naked body.
It wasn't long after that that Nagatoro felt her sister's thrusts rapidly speed up, a very clear signal that she was reaching her peak. A few more thrusts, and Nagatoro felt her sister's cock push all the way inside her yet again, only this time she stayed there, locked in place as she popped. Warm ropes of seed pumped into the deepest parts of Nagatoro's cunt, inner walls painted white as a symbol of their incestuous union. Nagatoro was certain her sister had impregnated her, pulling her in for a passionate kiss, which her sister quickly reciprocated.
She couldn't wait to tell the other girls the good news.