In Big Brother to the Rescue!, Froakie was shown to have befriended Grimer, who had given its home cave for the newcomer to inhabit. Unfortunately, this had also resulted in Grimer unintentionally polluting Cerise Park's water stream by bathing at the water source.
Frogadier is a very eager Pokémon and enjoys battling, as shown when it saw Lucario and Cinderace battling, and wanted to do the same. As is usual of its species, Frogadier uses its Frubbles to defend itself. This made it difficult for Goh to capture Frogadier without Bonnie's help.
At Cerise Park, Frogadier prefers to stay in dark places, like a cave, which is why Goh's Grimer had given up its home cave for it.
Frogadier, as a Froakie, was the last Pokémon belonging to one of Ash's friends to evolve onscreen.