Masamune works as a Host, and is responsible for introducing Hotaru to the world of "Survival Games". He, together with his childhood friend, Tooru, form an alliance called the "Toy ☆ Gun Gun Team". He is unaware of the fact that Hotaru is actually female. To repay the damages caused by Hotaru to the club at which he works at, he offers her the chance to become a member of his team. Because of his past, he has abandonment issues, which later cause him to kick Hotaru out of the team, fearing she will leave him like his former friends/teammates and mother did. However, after Hotaru helps him face his past through a one-on-one challenge, he lets her rejoin. After Hotaru rejoins the team he develops feelings for her, but struggles with them as he does not know that Hotaru is female. There was a moment in his past where, after being abandoned by his mother, he grew suicidal. Nagamasa introduced him to survival games to convince him to live on.
