Kyoumi Shiroyama

Kyoumi Shiroyama (城山 京美（しろやま きょうみ）Shiroyama Kyōmi), also known as Queen of Hearts, was a summoner and one of the Shiroyama Siblings, the 15 children gathered for the Fifteen Siblings Project.

Appearance
Kyoumi Shiroyama is a high school age girl. During her time in the Fifteen Siblings Project she wore a cosplay of the White Queen she had made herself, though her white dress was decorated with several dangling red, green and yellow plastic decorations in the shape of the four card suits (hearts, diamonds, clovers and spades) in a necklave and multiple bracelets. The White Queen's usual flower hair decorations are also replaced by a pink heart decoration.

Personality
Prior to the White Queen's summoning, Kyoumi was a cheerful and friendly girl, who despite settling in a group with Kyousuke and Biondetta Shiroyama during the project's initial stage readily visited all the other groups to offer her sewing skills to her siblings, accepting requests to make personalized clothes for any of them just because she liked making clothes. She also enjoyed teasing her younger siblings like Kyousuke and Biondetta.

She had the habit of adding the word "deadly" to her sentences.

Abilities
Kyoumi Shiroyama's abilities and style as a summoner are unknown, though they can be presumed to be quite high given her position as one of the children gathered for the Fifteen Siblings Project. She was also talented at making clothes, a skill she used to make clothes for several of her siblings, like Biondetta. She was skilled enough to replicate the White Queen's dress for her cosplay from the various paintings and scupltures in the Mock Battlefield.