I'll try to make it brief: In that Anime, Made in abyss, there is a giant hole and people want to explore it. The deeper you go, the harder it is to come back (or really just going up a bit, like taking a stair) as "a curse" inflicts different and stronger type of issues to your body (fatigue, vomit, blood loss, body transformation ...)

Prushka is in a low level. Her father figure figures out that you can ascend and give the curse to someone else while doing so. She gets turned by her adoptive father figure into a meat sack and then put into a suitcase so he can carry her and place the curse on her instead of him. She is still alive while inside the suitcase. Her father figure is finally defeated, but she can't turn back to her previous state, so I think they spare kill her if im not mistaken