The big night for inseminating Emma’s sister arrives

When the sisters planned the initial insemination - they told each other that it wasn’t really sexual - they just needed your cum, and this seemed like the easiest way to get it. Emma knew you would happily donate your cum willingly and knowingly, but then it might be weird for you or her sister if you knew that Emma’s niece or nephew was your biological child. Keeping you ignorant seemed the safest bet.

Emma warned her sister about the size of your cock, but her sister thought Emma was exaggerating. She hadn’t really gotten herself mentally or physically prepared.

That’s how Emma’s sister justifies how she lost control - how she got more sexually invested in the experience. She was carried away by excitement over your cock. She got a little (or maybe a lot) crazy with horniness, She knew she’d have to blow you as part of the deal, but she hadn’t expected to get so into trying to take as much of you into her mouth as she could fit - she hadn’t planned on riding your face. She didn’t think she’d cum at all, since she never cums while having sex with her husband.

Most of all Emma’s sister hadn’t expected to kiss her own sister at all. But Emma was bold and made a move, and it was just a small thing at first. Sort of teasing. They touched each other’s breasts a little. But that was it. Nothing serious. There was a line - Emma’s sister didn’t think they had crossed it.

She didn’t know how determined you were to obliterate the line tonight.