Nonono, Sunny.
You’d be taking the wrong approach there.
Starting from the top you’re quickly gonna cut something vital, like a coronary, a lung or the heart.
Then she’ll just go limp and you may as well just cut a bag of processed meat and get the same result with less of a mess.
Better to go ‘crotch to throat’.
She’ll be conscious for longer and in far more agony, given you start at a real sensitive region where pain lingers for what feels like an eternity, only increasing with every inch you proceed further up.
And if you want to go the extra mile, use something more jagged, like a bread knife or one of those survival knives with a serrated back.

Bro this went from Pippamena to Lesson Zero Sunny.

Raspberries into the chest fluff would be more pleasant I think.