Teru Momijiyama is a 14-year-old Japanese superhero who goes under the name: Shy. She stands at 4'11, weighs 94lbs, & has black hair, black eyes & wears square eye-glasses

Aside from her superhero outfit: she commonly wears her school uniform, consisting of a: White long-sleeved shirt with a dark-blue sailor-collar with a red cravat & dark-blue cuffs. Along with a knee-high dark-blue pleated skirt, knee-high black socks & white shoes.

As Shy: her hair turns white & she wears a white visor instead of glasses with a white sleeveless leotard with triangular collars, a black gas mask above her clavicle & a white hood with a double tail with a red interior, a black belt with a white buckle with a "S", long white gloves & the Heart-Shift Bracelets on her wrists, black thigh-high socks and white thigh-high boots with black soles.

Teru is extremely shy & has trouble dealing with crowds & people in general, just as she generally thinks negatively of herself, especially after being chosen as Japan's Hero. As her ability to talk in public is very poor, she also has difficulties to raise her voice or even talk normally with many people at once.

Her self-esteem is noticeably low & she often doubts her ability to save people. But she is very kind & innocent, the type who can't say "no" to people. She still cares a lot about the people around her & martyrs herself for them. Teru tends to think too much, but tries to act when necessary.

Teru has many fears & often lets herself be taken away by them although she tries to overcome them. She cannot speak to new people normally without blushing & stuttering, but she is always ready to help people. Even if she is afraid, she wants to be a better Hero and has the determination to get stronger.

As any Hero, Teru has possession of a pair of bracelets which syncronizes her Heart spirit into power. These bracelets also grant her the ability to conjure flames through her bracelets & Heart power.