Souta Hori (堀 創太 Hori Souta) is Kyouko's younger brother and the son of Hori Yuriko and Hori Kyousuke . Miyamura first encounters him when he is attacked by a dog, and brings him back home, meeting Hori in the process. Hori uses Souta as an excuse to invite Miyamura over a second time.
Souta is an obedient child has a close relationship with his sister. He is also very fond of Miyamura and respects him like an older brother. When he first meets Miyamura, Miyamura describes him as "level headed" due to the fact that he is able to remember his address.
Being a child, he can be very direct and is not embarrassed to bring up topics that Hori can't mention. He expresses happiness when he sees both Hori and Miyamura wearing rings, thinking they are getting married. He is also surprisingly perceptive, noticing that Hori and Miyamura have feelings for each other before they do, which prompts him to stay late in school so the two can have more alone time with each other. Unfortunately, Hori and Miyamura mistake this as Souta entering his rebellious stage early.
Yuna calls him a crybaby, as he tends to cry easily over little things. He is very interested in anime, such as Hurricane Star and is frequently watching anime or singing the songs when Miyamura visits.Because of this, Hori also unknowingly memorizes many of the song lyrics as well, which she finds embarrassing.
Souta first meets Miyamura after he trips upon seeing a dog, and Miyamura brings him back Hori's house. Souta becomes "obsessed" with Miyamura's visits.
Souta's older sister. Souta has a typical relationship with Hori, just like any brother and sister they love each other and bicker sometimes. He usually looks to his sister when facing problems, since their parents are usually away. He loves his sister which was shown when he asked Miyamura if he and Hori always "make love" and that shows that he doesn't want to give Hori to him. But, in the end, he lets Miyamura have some of Hori.
A friend and classmate to Souta. When she is first introduced, she is shown yelling at Souta for "being a crybaby." However, her relationship with Souta soon becomes more friendly and she comes over occasionally to play after this.
They have a good relationship. When they first meet, Miyamura rescues him from a dog and brings him home. As a result, Souta becomes extremely attached to Miyamura. He views Miyamura as an older brother figure, typically addressing him as "Ni-chan". Whenever Souta needs help Miyamura is his second choice, that is if Hori isn't available. He usually believes anything Miyamura tells him, which is shown when Miyamura tells him that honour students can shoot lasers out of their eyes. It's also evident he enjoys his company, as he usually asks Hori if Miyamura will be coming over, becoming disappointed if he finds out he is not.