Toru is a fairly short girl of a slender build with a completely invisible body. She is only identifiable through held or worn objects, like pieces of clothing and accessories. She claims to look like Yang Guifei and Francis Xavier mashed together.
Her hero costume consists of baby blue gloves, decorated by pale pink lines, and light brownish-gray lace-up shoes.
Her winter costume includes plain knee-high boots and slightly thicker-looking gloves with a different color scheme and design.
Winter hero costume
Toru is a bubbly, cheery, and easygoing girl that does most things with an upbeat attitude, even if manipulated to do so. She is very socially eager and appears to like shopping. Her room suggests that she likes plushies and other cute things.
She believes that taking off her clothes during battle is a tactical advantage, much to the awkwardness of those around her. That being said, she seems blissfully unaware of what it means to be invisible, such as displaying slight embarrassment at the idea of being watched undressing; a trait that shows up even when she's wearing her hero costume, which features almost no clothing in the first place.
In general, it appears Toru's invisible body is primarily used as a source of comic relief.
Hand-to-Hand Combat: Toru's primary fighting style consists of directly attacking her opponents with a barrage of punches, taking advantage of her total invisibility to launch surprise attacks that are extremely difficult to guard against.
Invisibility (透明,Tōmei?): Toru's Quirk turns her body completely invisible. It is unknown if it is permanently active or can be activated and deactivated at will, but has been shown to stay invisible while unconscious or asleep.
Light Refraction (集光屈折,Shūkō Kussetsu?): Toru bends light through her invisible body, blinding those who are nearby.
Toru's stats, according to the Official Character Book
Originally, Toru's costume had more trinkets to it than just a pair of gloves and boots. She was supposed to wear some sort of mask with a smiling face on it, and her gloves were meant to have mirror-like objects tied to them.
Toru's given name, "Hagakure", 葉隠, means "hidden in leaves". "Toru", 透, means "transparent".
Toru was supposed to be a male character at first, but Horikoshi changed her into a female because he thought a girl having an invisible body was a funnier concept. There was also a lack of female characters at the time.