AppearanceEditSenri is described as having medium length black hair and red eyes for most of the series but towards the end, he chooses to dye his hair, but dyes it back. His regular outfits consist of his school uniform, or his casual clothes.
At school, he is usually cold to people sometimes to the point of not even bothering to remember the names of people that don't interest him. With Shiro/Hime's help, he starts to warm up to his classmates. For the end of the term assignment, when groups of 5 have to get together to voice act a play, Senri invites everyone to his house to practice. He later attempts to take back the offer but, after seeing how happy everyone is about it, he decides not to.
Senri is an extreme tsundere. He loves small animals, especially cats. His house is filled with dozens of cats that he's picked up off the street, including Katerine, a very motherly cat, and Gustaf, one of the kittens Shiro helped Senri collect on the rainy day they first met and doesn't interact with anyone besides Katerine.
Senri didn't always hate his mother. In fact, he wanted to be just like her when he was a kid. He too loved acting, just like his mother. He would also forget about everything else when he was in the process of becoming his character although he wasn't as overly obsessive about acting. His mother would go so far as to move houses just so the background fit the character she was portraying. She even put acting above her family including Senri and his father. Senri grew up believing that everything was just an act, that everyone was just acting. His acting eventually became a huge problem. In elementary school, he befriended a boy named Imaizumi who was very shy and didn't have any friends. Everything was great until one day, Senri thanked him for 'acting as his friend.' He was deeply hurt by this, as he realized that Senri was only acting as his friend, and that their friendship wasn't real from the beginning. Ever since that day, he and Imaizumi never saw each other again.
In middle school, Senri befriended another boy named Kazuma. Kazuma also liked to act, so when Senri asked him if they could act as friends, in order to improve both their acting, he agreed. They acted as friends for some time, but eventually Kazuma began to see Senri as his real friend, but for Senri, it was still all just an act. Their one-sided friendship came to an end when Kazuma had to move schools. He told Senri that he really enjoyed spending time with him, and Senri replied by telling him that he was thankful that Kazuma always acted as his friend no matter what. Kazuma was angered by this because even after all this time they spent together, Senri still thought that they were acting. Kazuma told him that he was nothing but an empty vessel without real human feelings, that except for acting, he had nothing left. After that, he left and Senri never saw him again just like with Imaizumi. Even years, those words still burn in the back of his mind. Ever since that day, Senri started to put up a barrier between himself and everyone else. He didn't want to hurt himself or anybody else ever again. He started to hate his mother from then on, always believing that it was her fault that he became like this.
When he first met her at school, he initially didn't like her because she didn't interest him in the least. But, when she stepped in for Michi and played the Prince role instead, her voice was so great that Tsukino, the girl that was playing Snow White passed out. Since it was an emergency, Senri stepped in and took the Snow White role instead. But, he later regrets his decision to do so. Ever since then, whenever he sees Hime, he would often pat her on the head or hug her. This is because she reminds him of an old cat named Gonzales that he used to have. Usually this only lasts for a few seconds before he snaps back to reality. Because of this, he tries to stay as far away from her as possible. Since they sit next to each other in class, staying as far away as possible isn't an option. He also calls her ugly and acts quite cold towards her.
Although he is cold to Hime, he is much nicer to Shiro who is actually Hime, but he doesn't know. He meets Shiro when he was walking home carrying a box of kittens. Since it was raining, he invited her into his apartment. He was reluctant in the beginning to let Shiro get close to him because of his past, but figured it was okay since they wouldn't become good friends anyway. After spending some time with Shiro, he starts to warm up to her. He even starts to make food for her for whenever she would come over. He later finds out that Shiro is also a male seiyuu, that they have been doing multiple jobs together, but he just didn't realize it because they have been doing their recordings seperately.
When Hime is warned by Yamada to not get too close to Senri for fear of her real identity being discovered by him, Hime takes the warning seriously, seeing that if she were to be discovered her dream would come to an end. Because of this, she stops seeing Senri for a while. This makes him upset, because Shiro is the only person he's ever opened up to since Kazuma. Meanwhile, on Hime's side, she realizes that she just can't leave Senri alone, so she goes to his side knowing the risks that she will be taking by doing so. Later on, when he discovers that Shiro is actually Hime, he is shocked in the beginning but he forgives her for hiding such a big secret when he realizes that he is in love with her. At the end of the manga, he is a director for Lovely Blazers and is seen to have a matching ring with Hime.