A proposed scenario.
A little borrower girl is in love with a full-sized man. But he's clearly interested in a full-sized woman, not some little borrower. Eventually, the night comes when the man and his girlfriend are going to get it on. The borrower has to keep this from happening! They get out the condoms and open one, but the man sits it down before putting it on, waiting while his girlfriend gropes him.
The borrower sees her chance! She scurries from her hiding place, pushing the box of condoms off the top of nightstand, letting it fall behind it and out of sight. She then rushes to get rid of the open condom. The man, kissing his girlfriend as the moment comes, reaches for the condom without looking. He pulls it back and the borrower trips over it, falling into the ring, and as he lift it, she tumbles down into the condom. He's so excited for what's to come that he even ignores that the condom feels tighter than expected and warm around him. He'll have to ask his girlfriend what kind of condoms these are later!
The borrower girl feels panic and excitement. She's wrapped tight around the cock of the man she's always wanted! But she knows what's about to happen, too. As the man fucks his girlfriend, the borrower's front is brushed back and forth against his cock and her back presses against his girlfriend, stimulating them both like a living cock ring. She wanted to stop them from getting it on, but instead she only helped make this be the best sex either of them had ever had. She tries to ignore it, just focusing on the feeling of the man she loves, taking satisfaction in knowing she's the only girl here feeling his bare skin.
When he cums she's excited and aroused. Proud and happy. Cum fills the end of the condom, pooling warm around her feet. Then she panics as he cums more than she ever expected, sticky white slime flooding all over and around her, filling her mouth and covering her whole body. It would be a wonderful way to go, but he finally pulls out of his girlfriend and pulls off the condom, tying the end in a knot as he kisses his girlfriend, then dropping it on the nightstand. Without his cock filling most of the condom, the borrower is able to breath again for now, sitting up to her chest in the cum-filled condom she's trapped in.
She licks her lips. This is the cum of the man she loves. And she helped make him release it. Then she sees that the man and his girlfriend enjoyed it so much that they decide to go a second round. But they can't find the box of condoms, now hiding behind the night stand! Fuck it, his girlfriend says. That was amazing, just give it to me raw! The borrower's plan backfires further as due to her hiding the condoms, the man she loves is going to cum inside another woman. She watches them go at it, masterbating in the cum-filled condom she's trapped in, at least knowing that every time she pushes her fingers into herself, she's also pushing more of his seed into her, and so she accepted it well before his girlfriend did.
