Yōto Yokodera

The protagonist of this story. His first-person pronoun is "boku." He is a second-year high school student attending a school in Tokyo, living with his parents and his older sister, Yotsuba. He has poor grades and is very forgetful, but he looks up to Oscar Wilde as his spiritual mentor and occasionally quotes him.

He constantly thinks about girls, and from elementary school, his actions, driven by his own desires, were often misunderstood as good deeds. He relied on pretenses to maintain these misunderstandings, leading people to mistakenly believe he was a serious person. He joined the track and field club with the impure motive of peeking at the girls' swimming team, whose activities were adjacent to theirs. Due to his daily attendance, he was regarded by Tsukushi, the club captain, as an enthusiastic member and was even appointed as the next captain. However, he lacked motivation and, troubled by the "Stony Cat" rumors, made a wish to transfer his pretense to Azusa. Since then, his true thoughts (including lust and material desires) came out of his mouth with no filter, earning him the nickname "Pervert Prince." Consequently, he was demoted to provisional member in the track and field club and was often avoided or mistreated by others.

After reconciling with Azusa and regaining his pretense, he decided to protect Tsukiko as a "brother" by using the Stony Cat's power to discard his sense of shame, resulting in his true thoughts occasionally slipping out again. He is kind-hearted and considerate of girls' feelings, often trying various methods to respond to their affections towards him.

As a child, he was fond of Tsukasa, the mother of the Tsutsukakushi sisters, who was a caretaker at the daycare he attended. He frequently visited the Tsutsukakushi household. Meeting his future self and Tsukiko from the past allowed him to connect with the younger Tsutsukakushi sisters. He transferred his "memories" to Tsukushi, who sought memories of her mother, at the cost of losing memories of people he no longer interacted with daily.

As a track club member, he is good at running and applies this skill to escape quickly.

The author, Sagara, describes Yōto as a protagonist who would typically evoke distrust from readers, but by infusing lines like "Girls are cute" or "I want to see underwear," he manages to write Yōto in a lighthearted manner, even during serious plot developments.

Yokodera's "Younger Brother" (Yokodera Otōto)

Tsukushi, who is extremely obsessed with her younger sister, Tsukiko, concocted the existence of an imaginary twin brother as Yōto's disguise because she couldn't direct her frustration at Yōto, who was often with Tsukiko. When playing the role of his brother, his first-person pronoun changes to "ore."

While Yōto is humble towards Tsukushi, his "brother" freely uses offensive terms like "idiot," making the disguise obvious to others, although Tsukushi, who trusts Yōto, sees them as completely different people. Tsukushi, seeing him playing with Tsukiko and Azusa, perceived him as an "immoral two-timing man" leading her to antagonize him until events in the second volume where she started to develop feelings for him. This persona is sometimes brought up when convincing Tsukushi.