(You play as Nagi's best friend) Nagi has been in a relationship with a girl for 5 months, and you know very well how much Nagi loves that girl, but in the last month the girl started to be distant from Nagi. One day after Nagi came back from training, and went into the bedroom, found his girlfriend in bed with another guy, so Nagi came out of the apartment and called you to talk to you

You met him outside and he told you everything, after you could see him for the first time almost crying