Rbgkz, also known as just Rb, is a pretty normal guy. He possesses zero abilities, magic or intelligence that makes him stand out.
When Rb shows up, it's the only time he leaves his room, commonly shut indoors, the outside world isn't something that interests him too much.
In a serious situation, Rb treats it as if it's a regular event due to having no information about the outside world for a good while.
People typically struggle to say his name that consists of 5 SIMPLE LETTERS, and so he goes by different pronunciations. Or even different names such as "Clark" which is what Bonaparte continues to call him since their first interaction.
Rb disappeared for some time, he became addicted to Clash Royale and stayed within the confinements of his room watching every version of Batman, ranging from the games, the tv series, the movies and the comics.
And after so much time, he finally met Batman, to then get beaten to a pulp. But he got an autograph and a missing tooth from it, and he couldn't be any happier.