Benji is a character who appeared in the episode "Mountain Time" as part of his day-to-day life in the mountains.
Benji works with his father in the Mountain Patrol, where they use Ledian to help protect the area. His father trains their Ledian using a Pidgeotto that creates strong winds to simulate real mountain conditions—basically a live practice dummy for the job.
When Ash and the group showed up, Benji was eager to demonstrate his training techniques in the woods. Things went sideways fast when an unusually powerful wind hit and swept Benji's Ledian away. Turned out Team Rocket had brought along a vacuum machine that was causing the chaos—and it had already sucked up Pikachu and Togepi. Benji sent his Ledian after them, but the machine's suction was too much to fight. Luckily, a real mountain windstorm knocked Team Rocket's balloon off course and crashed them into the peaks.
From there, Benji became invaluable. He and Ledian guided everyone through the mountains and helped track down their stolen Pokémon. When they finally spotted Team Rocket stranded on a precarious rock outcropping, Benji rigged up an improvised zip-line rescue using a rope, net, and Ledian's help. Things got hairy when a rock started dragging the line down, but Ledian powered through and got everyone to safety.
Team Rocket tried making off with Pikachu and Togepi again, but Benji's father cut them off. The two of them combined their Ledian's strength to recover the Pokémon once and for all. As night fell and the stars came out, Benji's Ledian's back spots lit up in the darkness—a beautiful moment that made his father decide to officially promote him to Officer of the Mountain Patrol for his heroic work that day.
Content compiled by AnimeList.moe from publicly available sources.