Preface note: 'the girl' and 'she/her' are two separate entities, and each is always referred to by the same pronoun.
She called out, just once, for the girl to send her back home, th-this was a one-way journey, and she was still unsure, hesitant, but the girl insisted, and she was slowly, slowly, preservingly split down the middle, and separated from her other half. She whispered a goodbye to her other self, even though she knew they'd be together again soon, but, both of them would be changed forever, right? She suspected what sort of future there would be, but had only heard of it, from here and there.
The girl returned, and softly, but firmly embraced her...Was this what it's come to? A long, thin tool was set against her sensitive skin, it was cool but she was even chillier, as the nature of her home had been, too. She wanted to return, but...there was no sense in waiting forever, this was something new to her. She solidified her composure even as it pressed in sharply--! This, this definitely wasn't all there was to this, right?! It left her and shifted, pierced into her one more time, and then two more times, and there was a whisper that she only needed to go through this once, but f-four more times after that! And... there were even more but she, numbing and dizzy and with no choice but to trust the girl, couldn't count anymore by the time she realized that it had stopped. Shocked and nervous, she shivered and waited for more.
She gazed up at the girl, apprehensive anxious, and curious. The girl gazed back down, smiled, and swept the tool through the air again. She flinched, alert and leery--anyone would be scared! But the girl set it gently down on one of the walls in her heart...an intimate place...and held it there for a moment before slowly sliding it up and down that barrier, feeling for a weaker spot in it, then finding one near her center and pushing out, down, then sideways and across, and down again, until she was divided from herself even while she was whole... It was completely different from before, and she didn't even notice the girl gently working on the other side of that wall. W-wait! No, she'll fall apart if you do that! The girl set the tool down and let go of her, then made a vow, that she'd be exceptionally gentle in contrast to the rough severs that others of her siblings have probably gone through. She didn't like the thought of it, but there was some relief there too.
The girl returned to the fine motions of the blade's rounded tip, leaving her surely as intact as she could be through it all. She began quivering in anticipation, and she became more and more wet, shivering as her heart was lain bare, pulled apart at every once-smooth seam in her body by the time the knife was put down, with light sound that didn't matter to either of them. The girl cradled her and swept her away, her surfaces flushed and features unsteady. The girl rested in a seat and plunged a spoon deep into her body, squelching in her wetness and lifting out part of her heart, her mind, her body, the sensation was hard to bear! It was nearly too much, but she could only roil in the feeling silently, as her body made all the noise to be heard. One piece, no, two parts, no! Three bites, four more, and she lost herself in the ecstasy. All she could even recognize as herself was the last piece left as she was lifted from her casing and engulfed, inside and one with the girl, no longer individual but part of something so much more complete. She surrendered to the pleasure with all the other parts of her, united in mind and form, once again.
The last bite was the sweetest.