Suzume Yamada is the child of Chihiro Fujisaki and Hifumi Yamada. She has light brown hair cut in a messy bob, and dark brown eyes.
In her pony form, her cutie mark is shown as a sharpened pencil.
Suzume is a rather anti-social child, spending most of her time indoors drawing. She is a misanthropist, and is very scared of being in social interactions. Her few close friends do see her as something different- Her true personality resembles that of Hana Naegi.
Her upbringing may have lead to her becoming who she is. Being the child of Chihiro Fujisaki and Hifumi Yamada, she never was forced to go outside or interact with humanity. The only true interaction she had was with the people on Reddit forums or Tumblr blogs. So when she was suddenly thrust into a school life with hundreds of other people, she wasn't at her best.
Suzume, being a misanthropist, never really paid attention to love or any of the such (Unless you count the 2D world). However, when put into her new schooling life, she developed a bit of a crush on Yoko Kuwata due to her almost opposite personality.
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Suzume is first seen after Hana Naegi waking up in an empty classroom. Hana sees her only for a moment as she runs down the hall, confused and frantic. She's then seen again in front of the heavily guarded front entrance.