[1] A girl named Kojima (コジマ), also 14,[1] has the nickname "Hazmat" and receives bullying from female students.

[1] Kojima chooses not to take baths,[7] has clothing that is not clean, and keeps her hair in an unkempt state.

Lily Meyer of National Public Radio (NPR) states that Kawakami has a sympathetic view of Kojima.

[7] Thu-Huong Ha in The Washington Post describes Kojima's view of bullying as "kind of religious, moralistic".

[3] Meyer stated that Kojima is similar to Franny Glass, and that she drags down "Eyes", being unable to provide "true friendship or solidarity".

[4] Momose (百瀬), who serves as Ninimoya's assistant,[4] tells Kojima that bullies act due to the fact they are able to do so.

[4] Meyer wrote that Heaven is "simpler" than Breasts and Eggs (the English version of Kawakami's Natsu Monogatari) and that it is "a raw, painful, and tender portrait of adolescent misery" that "is very likely to make you cry".