Raichu is incredibly affectionate and amiable. She's so friendly, that she is always eager to share any berries she has picked with her friends. However, this also renders her oblivious to the degree of pestering others unintentionally. She is also friends with Ash's Pikachu and cares about him, as shown when she became depressed when he was captured by Team Rocket.
After Goh was taunted by the wild Pikachu when he was trying to catch one, Raichu, as a Pikachu, appeared and offered Goh and his companions Pecha Berries. In this time, she quickly befriended Ash's Pikachu before being caught. When Goh hugged her after the capture, she electrocuted Goh. Soon, she asked Goh and his companions to come along, and led them to a massive group of Pikachu, digging the walls to find something. After one of the Pikachu there dug up a Thunder Stone and evolved into a Raichu, she dug up a Thunder Stone and gave it to Ash's Pikachu, to which he strongly refused. They chased to behind a large stone and a blue light appeared, making Ash worried. A male Raichu appeared from the stone, but then the two Pikachu continued chasing in the background, much to Ash's relief. She gave the Thunder Stone to Goh and re-befriended Ash's Pikachu.
Later, she gave Pecha Berries to Team Rocket's Jessie, James, Meowth and Wobbuffet, not knowing that they were villains. Shocked, Goh quickly rushes to grab back Pikachu explaining to her that they were the bad guys. Then, Team Rocket take out their giant Pikachu Vacuum Limo and capture a lot of Pikachu. When Ash and Goh try to stop them, they get upset and use the rocket prize machine and receive Minccino and Buneary. They end up capturing all the Pikachu except for Goh's Pikachu. After they successfully got Ash's Pikachu and ran off quickly, she went away offscreen feeling downcast. Goh later found his Pikachu, sitting on a rock, depressed. After Goh asks to rescue the Pikachu, she agrees happily. As Goh's other Pokémon on hand was battling Team Rocket's Buneary, she tried to break the glass of the mecha, but to no avail. Meowth later found her and tried to have to capture her as well by getting her into the pipe, but she did not loose herself to get into the pipe until she asked Goh to toss the Thunder Stone into the pipe along with her, allowing her to evolve inside the pipe.
Upon evolving, Raichu destroyed the pipe of Team Rocket's mecha, thanks to her grown size, allowing the collected Pikachu to escape. Raichu tried to hug Ash's Pikachu, but she accidentally knocked him off. Soon, they were thanked by the wild Pikachu and Raichu.
Back in the Cerise Laboratory, Raichu offered the Pokémon in the lab, Professor Cerise and his assistants some Pecha Berries. She also gave some more to Pikachu and Raboot, but they refused once again. She also tried to give some to Sobble, but Sobble managed to get to Goh and turned invisible. Goh sent Raichu to give Pecha Berries to the injured Suicune to cure its poison, also to calm it down.
At the Cerise Laboratory