Robert is Weda's trigger-happy bodyguard after she, Hare, and Guu move to the city. After graduating from high school, he arrived in the city on his own, only to be beaten up one night. He was later found by Bel, and it is through her that he ultimately secured his job.
Initially, Robert does not get along with Weda, openly claiming that she is unworthy of Bel's love. However, his attitude changes after the two work together to foil a bank robbery. Episode 23 suggests that Robert may harbor romantic feelings for Bel, though this is never directly confirmed.
In addition to being dangerously trigger-happy, Robert is highly paranoid and unstable. At one point, he even attempts to kill a boy who had bullied Hare, forcing Hare to intervene and protect his own abuser from Robert—an incident that highlights just how unhinged Robert can be.
(Source: Wikipedia, edited)
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