|Appearance||Period 34 & Period 35|
Kei is an average, good-looking young man with slanted eyes and spiked, light-colored hair. He has a gentle face.
Kei is a cool-minded and friendly young man who enjoys teasing his close friends. He cares deeply for Rui and does his best to keep her happy, but he attempts to cover up his true feelings for her by claiming to be worried about someone like her. Everything he does is for her sake. He is also extremely well-liked by others and has a large group of friends.
Kei first appears in a flashback, being shown turning down Rui's confession after revealing to everyone that he had to move due to his dads job transfer. Since then he began to avoid her, unaware of how terrible it made her feel. Once Rui uses the Hell's Clock she is taken back to the moment when she confessed. Kei expressed concern in her spacing out and he attempted to bring her back to reality by reminding her that she wanted to tell him something. Their conversation ended after she claimed it was only to ask that he calls her when he returns during the holiday.
The following day was spent honoring Kei at school with a party being held after classes ended. He approached her to ask what she'd like as a souvenir and noticing how upbeat he was, Rui asked if he'd be lonely at all. Kei teased her by asking if she would miss him, then he confides in her by saying that he might get lonely, but this is why he plans on having as much fun as possible. His words struck a chord with Rui, as she recalls how he was always positive and looking forward in comparison to herself- who remained stuck in the past.
Kei later met up with Rui when she returned with snacks for the party, and he mentioned that one of her friends told him of her feelings for someone. Rui was stunned by this, and Kei's playful attempts to help her by asking who it was only made her infuriated. They get into an argument, ending with Rui telling Kei off, leaving him to head back to the party. Rui narrates that he ended up enjoying himself while she was left with remorse yet again.
The following day, Kei had paid a visit to Rui's home to deliver some flowers to Jiro's grave. Rui remembered when she had been mourning her beloved dogs death and blamed herself in the past. Kei hadn't liked to see Rui so upset, so he attempted to cheer her up by claiming he saw Jiro in a dream. He said he was very happy and had a lot of fun, and his life with without regrets. He then presented Rui with flowers, saying that whenever she was sad Jiro would give her a flower to make her feel better. This memory had been what caused Rui to seek out Kei, who had been waiting for his bus to arrive that would be taking him away.
Kei was surprised when Rui called out to him from across the road, and he turned to her as she attempts to express her feelings. Neither of them expected the large, oncoming truck approaching, and in an instant Kei shoved Rui out of harms way- being hit by himself and left laying on the ground, with blood seeping from his corpse as Rui cries and tries to wake him.
A year passes since then, and as Rui recalls various other memories with Kei as she asks his mother permission to visit his room a final time. She was shocked to find out that he also had a Hell's Clock in his possession. As she considered using it, the Ghost who hands the clock out appears, and grants her permission: but only if she gives her something in return.
Rui agrees, and was taken back to the day when she confessed how she felt to him, with the event playing out the same way as it did the past two times. Rui was in tears seeing Kei alive and well, and he reminded her that she wanted to tell him something. She bluntly asks if he used the Hell's Clock, alarming Kei for a moment before he reveals that he never used it- but he had planned on it. He wanted to see what the future would be like out of concern for her, but in the end it felt wrong and he couldn't bring himself to do it. He didn't want to rely on such a device to see the future because he is sure she will be okay. He has faith in her.
Touched by his words, Rui decides she must be brave, and she loudly confesses to him again. This time Kei appears surprised, but Rui quickly intervenes by saying that he only sees her as a childhood friend- and she is okay with that now. She just wanted him to know. Before Kei can respond, the ghost reappears, revealing that she will be taking Kei's life away as payment. Kei is stunned and he asks Rui if she used the clock, and she confesses that she has. She apologizes for being so weak, but she had decided that she wants him to see her as the strong person he knows she is, and she thanks him for always being by her side.
Stepping on the rails of the fence, Rui asks that the ghost takes her own life as compensation and allows herself to fall off of it.
Since that day five years ago, Kei has remained there and every day he pays Rui a visit at the hospital. She has been in a coma since the incident, and while he visits her, the empathetic staff members can only watch him with remorse. Kei promises that he will remain by her side though and sits down the bouquet of flowers he got due to today being the official anniversary of the incident. No matter how long it takes he will remain by her side.
To his and the staffs surprise, Rui suddenly awakens to see him standing nearby. They happily embrace as the ghost takes off with the Hell's Clock.