After getting separated from the group while traversing Reversal Mountain, Bianca found a Pokémon Egg and decided to take care of it.
In Getting On Like a House on Fire!, the Egg hatched into a rambunctious Larvesta, who initially gave no reaction to his new Trainer, instead attacking Bianca with String Shot in order to keep her at bay.
However, after Bianca saved him from a wild Scolipede, Larvesta warmed up to his new Trainer, although he still attacked with String Shot if she got too affectionate.
Larvesta was used as Bianca's last resort while battling a wild Glameow in A Glamorous Encounter! During the battle, it became apparent that Larvesta was much stronger than before, with Bianca explaining to Lewis and Nate that they had been training hard since the group split. Larvesta was able to stop Glameow's swift movements with Bug Buzz and then wrap her up with String Shot. When Glameow escaped from this and attacked with Slash, Larvesta countered with Flame Wheel, which ended up knocking Glameow out, allowing Bianca to catch her.
Larvesta can be described as a "lone wolf", preferring to go about his business alone. He can be quite distant, disliking the close-up affection he often receives from Bianca, which causes him to attack her in retaliation. Despite this, Larvesta is shown to care for his Trainer and works well with her during battles. Larvesta has a tendency to bite off more than he can chew, as shown in his debut episode where he challenged a Scolipede and had to be saved by Bianca.