Haruka is close to his older brother and cares for him deeply. Though it was pursuing Kazuki when he went to leave with his biological mother that was tied to the accident that left Haruka using a wheelchair he bears no ill will. They talk together in their room and their close bond continues even after discovering that the 'Sara' Haruka has been texting was, in fact, Kazuki pretending to be Sara.
Kazuki's school friend, Enta helps Haruka weekly with where he needs to go such as taking him to meet Sara Azuma. They talk about their concerns regarding Kazuki.
He is a fan of this TV idol watching her regularly and is under the impression that he knows her personally by messaging her via phone. He believes she is complying with sending him photos of her with the daily selfie requests. Haruka also wanted to exchange a secret greeting with her in person and when he meets the actual Sara, Haruka accuses her of being a copy after she failed to answer his question. When the truth of the matter is reached, Haruka interacts with her properly for the first time by receiving Kazuki's wig from her that he left behind.
A plump ginger cat who Haruka feeds with his brother. He is unaware that Nyantaro was someone‘s pet before Haruka stole him and proceeded to pretend that he was a stray cat for them both to look after.
Unlike Kazuki, these are Haruka’s biological parents who he gets along well with. They are fully supportive of his interests and take him where he wants to go in his wheelchair.