Get to know Heiya!

The experiences in the deadly games slowly make her stronger, and she alters her opinion on how she wants to live her life. What remains unchanged is her undying will to survive, as demonstrated during the Boiling Death game and further confrontations with the King of Spades.

Having met Aguni, Heiya reveals her soft and caring side. She develops feelings for him, and whenever he is in danger, she always attempts to protect him.

History

Prior to being transported to the Borderlands, Heiya was a high school student. In the flashback, she is shown walking around with her female friends, who were complimenting her nails, before a group of guys approached them and invited them to a BBQ party. Heiya refused, explaining that it was the anniversary of her mother's death, but quickly revealed that she was not bothered by it in the slightest, expressing her annoyance and disrespect towards her late mother. Rudely rejecting the guys, Heiya and her friends left, then grabbed some drinks and started gossiping, walking towards Shibuya. Suddenly, a loud noise interrupted them, and they saw the fireworks.

Next thing she knew, she was in a huge stadium, surrounded by other people, but none of her friends seemed to be nearby. There was a big screen, instructing everyone to gather in the middle of the field, and a white table with 17 phones. Heiya was the last to grab one, wondering what the "game" meant, and an older person advised her to clear the game if she wanted to survive. The game difficulty was revealed as Seven of Spades and the rule was to escape the venue. As soon as the ground started shaking, Heiya ran, and the underground geysers started breaking the surface and flooding the arena, one of them eventually erupting in front of her and causing her to fall down under the stadium. She lost consciousness, and then, as she woke up, she realized that her left shin had been impaled by a metal rod. Seeing dead bodies in boiling water, Heiya started panicking and crying but then tried to collect herself in order to free her leg from the rod. After covering the wound with her shirt, she noticed a vent leading up, so she crawled there in order to escape.

Having crawled out to a more open space, Heiya found herself on a rock and looked down at the boiling water. She noticed her mother standing there and calling out her name, asking her to come down. Unsure whether to trust the ghost, Heiya jumped anyway and ended up in a pool that was not hot, so she managed to get out of the building as the only survivor of the game.

Using a piece of metal as a crutch, Heiya arrived at a building. She noticed that her injury was becoming infected due to the color, so she got worried it would kill her and started looking for medicine. A drunk man in medical attire came up to her and stated that her leg was beyond saving, but he refused to help her for free and looked at her skirt, hinting at sexual intercourse as payment for his services. Desperate for help, Heiya agreed and urged him to do something about her leg.