From Bulbapedia, the community-driven Pokémon encyclopedia.
Diamond (Japanese: ダイヤモンド Diamond) is one of the male main characters for the Pokémon Diamond and Pearl story arc of Pokémon Special.
He is the funny man (boke) of the comedy duo, with Pearl as the straight man, but he is not as stupid as he looks. His appearance is based off of the male player character of Diamond and Pearl, Lucas. He is usually called Dia, but whenever Pearl is serious, he will call him Diamond, his full name.
Diamond is often apathetic and rarely not seen eating, traits that he shares with his Pokémon. He is, while not fat, much less active or athletic when compared to Pearl. However, he is always serious when it comes to food and is an expert Poffin maker. Whenever something doesn't make sense to him, he'll try and figure out. Diamond has a somewhat natural instinct to judge how a Pokémon feels and can be quite observant when something perks his interest.
A mix-up has them thinking they will gain a prize for escorting Platinum to Mt. Coronet. Platinum, mistaking them for her bodyguards, has given them Pokédexes, Pokétches, and starter Pokémon from Professor Rowan. Eventually, they are told the truth by Platinum's real bodyguards, although Diamond knew long before Pearl that Platinum wasn't a tour guide. He figured this out from various clues such as the fancy hotels, and Platinum not actually acting like a tour guide.
Diamond has a large amount of respect for Pearl; the two are as close as brothers. Diamond also has a not-so-small crush on Platinum.
However, Diamond has changed a lot from the beginning of his journey. He was convinced by Pearl to set aside their dream of becoming great comedians to protect Platinum until she finishes her journey after the incident in Veilstone City. On Iron Island, he received training from Riley in order to further his battling skill, which was lacking when compared to Pearl's and Platinum's.
- Bē: Diamond's first Pokémon. Often seen eating with him. Hides berries and other items in its fur.
- Rū: Received from Platinum due to the mix up. Diamond's strongest Pokémon.
- Pū: Given to Diamon by Byron after it took a liking to him.
- Rī: Captured when Diamond was heading towards Lake Verity after it stole Diamond's Map.