Planned Release Date: 2027

About This Game

Blasphemous Sister‑Obsessed Human Transmutation

Hollow Heart is a growth‑simulation game built on the theme of blasphemous, sister‑obsessed human transmutation. As the elder sister, you will do whatever you can to resurrect your beloved little sister who has died. Gather materials, strengthen her soul and body, and bring forth a sister who is ever more “perfect” and “complete.” At the end of this profane path, will you truly be able to reclaim the sister you once knew?

Human Transmutation

Your sister can be revived by offering a body and a sacrifice. To erase the sacrifice’s personality and anchor your sister’s soul, you must fuse different bodies together. Prepare stronger vessels and superior sacrifices to resurrect the ideal little sister.

Raising / Growth

After transmutation, your sister’s soul and body are fragile and short‑lived. Educate her, train her, and build a bond of trust as you face hardships together. If she reaches the end of her lifespan, use her remaining body as the foundation for the next transmutation.

Exploration / Combat

Venture out to gather the materials needed for transmutation and growth. Along the way, primitive creatures and humans bound by trivial notions of morality will stand in your path. Work together with your sister to overcome them and carve your way forward.

Mature Content Description

The developers describe the content like this:

This work includes depictions of sacrifices and mutilation of the human body.