Time Leap Revolver ~Kanzen naru Fukushuu~

Officer Seigi Wakaba joined the force for one reason: to hunt down the monsters who massacred his family and abducted his little sister. But years of dead ends have left him broken. That is, until a cryptic letter from his missing sister leads him to an old, rusted New Nambu police revolver. Pushed to the absolute brink of despair, Seigi turns the gun on himself and pulls the trigger. Click. Bang. He doesn't die. Instead, the gunshot hurls him backward through time, waking him up just moments before the tragedy that ruined his life. Armed with a gun that shatters the timeline, Seigi finally has a chance to stop the massacre. But with every leap into the past, a sickening reality comes to light: the masterminds aren't faceless criminals. They are the smiling neighbors and trusted police colleagues he worked alongside every day. Betrayed by his world, Seigi stakes his life on the remaining bullets in his cylinder. He will dismantle their conspiracy piece by piece, but when the smoke clears, who will the final muzzle be pointed at?