Sakamoto and Shin vs. Heisuke Mashimo is a fight that occured between Sakamoto, Shin and Heisuke Mashimo.
Prologue[]

Team Sakamoto breaks up
Sakamoto and Shin enter the airsoft tournament. Immediately the tournament starts, Heisuke shows off his impressive sharpshooting skill. Sakamoto and Shin immediately start to dominate the competition and prove that they're the team to beat. Lu, however then shouts out Sakamoto's full name, in celebration of their domination. Heisuke, however is skeptical, until Lu takes the picture of Sakamoto he had and shows him the similarities between the current Sakamoto and the one in the past, also saying the reason why he looks so different. Shin covers Lu's mouth, but it's too late. Soon, the team breaks up and guns are pointed.
Battle[]

The fight begins

Sakamoto and Shin being overwhelmed
The stalemate is soon broken by other paintballers who Shin eliminates. Heisuke retrieves his rifle from Piisuke, which surprises Shin. While off the ground, Heisuke shoots at Sakamoto. Shin is surprised due to the fact that Heisuke got a perfect target on Sakamoto's head despite his distance and position. Heisuke retreats in order to get more space. Shin wants to pursue him, but Sakamoto holds him back and tells him to focus on the tournament at hand. After dealing with the paintballers, Sakamoto and Shin begin hiding because of Heisuke. Shin wants to go and find him, but Sakamoto holds him back and wants to reveal Heisuke's position without revealing theirs. Sakamoto, however, is immediately grazed on his shoulder by a bullet which he barely dodges. Heisuke is surprised to learn that he dodged the bullet. He praises Sakamoto but Shin downplays it, calling the ricochet a fluke. Sakamoto soon corrects him, telling him that it was as if the bullet was meant to ricochet. Heisuke then tells them that the bullets are called triple rebound bullets and that their designed to ricochet. Shin questions Heisuke about his newfound determination to kill them. Heisuke responds ruthlessly, reminding Shin that they're assassins and that when he looks through the scope of his rifle, all he sees is a target. Heisuke shoots another triple rebound bullet. This one ricochets repeatedly, overwhelming Sakamoto and Shin. Heisuke then begins to reminisce about his life and how for some reason, he's always been a decent shot and how he got into the destitute state he's in. However, he was talking out loud and Shin heard him. He gives Heisuke advice and startles him, alerting them to his location.

The end of the battle
Sakamoto then prepares and throws a rock so fast, it completely destroys Heisuke's rifle. Heisuke, in light of Sakamoto's strength, gives up.
Aftermath[]
The airsoft tournament ends and Sakamoto's team emerges as the winner. Heisuke cries once again, thinking he's a failure, even as a sniper. Shin is surprised, even doubting that Heisuke's an assassin. Heisuke responds by saying that Shin and Sakamoto don't know how it feels to be weak. Sakamoto refutes this, saying that Heisuke's the greatest sniper he has gone up against in his life. Heisuke cries once again, this time over Sakamoto's acknowledgement. He then receives his share of the prize money, a measly fifty yen due to his shooting wrecking the town.