This is a gender-swap trope.
Zenin Naoko realized she had been reborn.
She'd finally become the head of the family, only to get killed anyway... She'd thought she might at least turn into some kind of cursed spirit.
The world was still moving along its usual course. The difference was that this world had its own "Zenin Naoko": an arrogant young master with feudal values ingrained to the bone.
As a scumbag, he really was a fitting counterpart to her. Aside from being a bit too stupid and weak, there wasn't much wrong with him.
After she was reborn, her original technique, Projection Sorcery, disappeared. In its place was the Ten Shadows Technique, the technique her clan had coveted for years.
If she'd had the Ten Shadows Technique before, would it have taken so much effort to become head of the family?
It's decided. Once she's grown strong enough, she'll happily claim the title of head of the Zenin family in this world!
After meeting her counterpart, the Zenin family's nasty young heir, she kissed him on a whim, just to mess with him.
Ah, even though he's her counterpart, it's so much fun seeing that pretty face go slack with shock at her shameless behavior.
But after the kiss, she realized something was wrong.
Their bodies had switched?!
She looked down at the arrogant young master, who was leaning against her in shock, his hands clutching the front of her clothes in fear. His haughty, upturned fox eyes held an expression of terror she'd never seen before.
Oh no. It looks like she's opened a door she shouldn't have.
Tips:
The heroine is a pig who was born female in a parallel world, became head of her family, and then died.
First, a warning: the heroine is a scumbag.
The pairing is selfcest. I don't know if it's BG or GB, since they can switch bodies. If that's a dealbreaker, don't read.
The soul in the female body (gestures) will be more dominant, since she was nearly thirty and had been head of the family.
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