Naoto and the other K4 members head to Karuizawa for Advanced Railway Security Force Training. Naoto is excited to hear that they'll have a course on operating an EF63 electric locomotive; but instead the instruction is on the EF63's predecessor, the ED42. Aoi accompanies him in shooting lessons and strength training, saying she doesn't want him to slow her down as they'll be working in railway security together, but Naoto tells her he's aiming to be a driver instead, leading to an argument.