Mafuyu and Yuki were friends for some time before they started dating in middle school; however, during their first year of high school, they had a fight which led to Yuki committing suicide.
Yuki Yoshida was Mafuyu’s childhood friend and ex-boyfriend, Yuki committed suicide approximately six months before the start of the manga series, Given. Yuki worked part-time upon entering high school, so that he could afford to buy himself a guitar. He is mentioned a lot by other people, mostly in reference to the rumours of him dating Mafuyu in middle school. Another speculation is that the reason behind his suicide had something to do with Mafuyu.
Their friendship started when Yuki asked Mafuyu if he ever speaks, to which he replied that when he speaks, his dad hits him. Later on, Yuki is seen standing by Mafuyu, while policemen are walking around Mafuyu’s house, seemingly to arrest his father.
Mafuyu, Yuki, Hiiragi and Shizusumi were all friends, and always seemed to be in their own world. Their friendship has been described as two magnets in the way that their personalities were opposite of the other. Yuki and Mafuyu started dating during their middle school years.
Yuki, Hiiragi and Shizusumi all went to the same high school and formed a band, while Mafuyu attended another school. Yuki revealed in the series that between school, his part-time job and band practice, he had no free time for Mafuyu. Fans are led to believe that this might be the reason why Yuki and Mafuyu fought later on.
During their first year of high school, Mafuyu and Yuki got into a huge argument. Yuki placed his hands on Mafuyu’s shoulders, only to be pushed away. Mafuyu shouted, “Would you die for me then?”, to which Yuki replied that he would do anything for Mafuyu.
A few days after the fight, Mafuyu went to visit Yuki, but found him hanging from the ceiling hatch in his bedroom. It was later revealed that Yuki drank a lot of alcohol that day and committed suicide. It has also been hinted that his suicide had something to do with the argument between him and Mafuyu. Yuki’s mother later gave his guitar to Mafuyu.