Kiichi

Bucky is a character of the day who appeared in The Dunsparce Deception (EP193).

He is a young boy who lives in Johto, in a small town between Ecruteak City and Olivine City. Bucky dreamed of catching a Dunsparce. However, he missed out on his chance to catch one when he was out of town, when a swarm of Dunsparce came through the area. All of his friends caught a Dunsparce during that time, Bucky ultimately being the only one who didn't get one.

When Ash and his friends heard about this, they decided to help Bucky out by searching for a Dunsparce. Eventually, one turned up. Bucky, using his Caterpie, battled the Pokémon and successfully weakened it. He threw his Poké Ball and caught it, leaving him very happy.

(Source: Bulbapedia)