So Sakura

So Sakura (26) Played by Ren Meguro (Snow Man). Tsumugi's boyfriend during high school. He was the captain of the soccer club. He started dating Tsumugi after they were in the same class in their third year, but around graduation, he developed juvenile-onset bilateral sensorineural hearing loss. He sent Tsumugi a short LINE message saying, "I have someone I like. I want to break up," and ended the relationship (it is later revealed that the "someone I like" referred to Tsumugi herself, not another person). He then cut off all contact with his close friends and disappeared. When Minato once visited him at university, So kept his distance, saying, "I don't need Tsumugi anymore, you can have her." He entered university on a sports scholarship, but due to his illness, he had difficulty hearing instructions and was misunderstood as having "no sense of cooperation." Finding it painful to continue, he quit soccer. He lost almost all of his hearing three years ago. He now works from home as a proofreader for a publishing company. Nana is the only friend he made after developing his illness.

Minato Togawa

Minato Togawa (26) Played by Oji Suzuka. A high school classmate of Tsumugi and So, and Tsumugi's current boyfriend. He is So's best friend and has always been concerned about So since he suddenly lost contact. When he visited So's family home after Tsumugi happened to see So, Moe accidentally informed Minato about So's illness. Even after Tsumugi and So resume contact, he initially avoids So, unable to fully process and accept So's illness.

Tsumugi's Circle

Tsumugi's Circle Hikaru Aoba (20) Played by Rihito Itagaki (Childhood: Toya Shimizu). Tsumugi's brother, six years her junior. A university student living with Tsumugi in Tokyo. Masaki Haruo (32) Played by Shunsuke Kazama. A sign language instructor. A regular at a pub Minato frequents. He began teaching Tsumugi sign language after giving a pamphlet for the school to Minato, who had just learned of So's illness.

So's Circle

So's Circle Nana Momono (27) Played by Kaho. A woman with a hearing impairment. She grew close to So after meeting him at a job-hunting support seminar for the deaf during their university years. She harbors feelings for So. Because she has never heard So's voice, she felt envious of Tsumugi, who had heard his voice and even spoken to him on the phone, and confronted her with these feelings. However, after speaking with Tsumugi again, she decides to let go of her feelings for So.

The Sakura Family

The Sakura Family Ritsuko Sakura (49) Played by Ryoko Shinohara. So's mother. She was the first to notice So's illness and took him to the hospital. She fell into self-loathing after the illness was diagnosed as likely being hereditary. She worries about So becoming isolated because of his condition. Moe Sakura (20) Played by Hiyori Sakurada (Childhood: Nono Obata). So's younger sister. A local university student. After So's diagnosis, she was the first to learn sign language to support him and mastered it quickly. Thinking that Minato already knew about So's hearing loss and that they were still in contact, she accidentally gave Minato So's contact information when he visited their home. Takashi Sakura Played by Tsuyoshi Rishige. So's father. He watches over the family from a slight distance but is the one who cares for them the most.