Susumu Kibayashi, also known by his stage name MC Kiva, appears as a supporting character in Detroit Metal City. He is a rapper who enters the story by directly challenging the band DMC to a music battle after fans of DMC attack one of his own fans. This confrontation forms a central conflict in his arc and highlights the rivalry between the rap and metal scenes within the series.

His background is marked by a notable contradiction between his claimed past and his actual history. Kibayashi asserts that he grew up in New York, but in reality he was raised in Japan and has a very poor command of English. This dishonesty about his origins reveals a key aspect of his personality: he constructs a false identity to appear more credible or impressive within the music world, much like the larger theme of fabricated personas that runs throughout the series. Additionally, he shares a personal history with the protagonist Souichi Negishi, as the two were classmates in elementary school.

In terms of personality, Kibayashi is devious and calculating. He is not merely a rival musician but an antagonist who actively works to undermine DMC and exploit situations for his own gain. He is cunning in his approach to the music battle, using strategy and manipulation rather than brute force. His behavior is often self-serving, and he takes pleasure in causing trouble for others, displaying a sadistic streak that adds tension and conflict to the story. His exaggerated streetwise persona, combined with his actual ineptitude in English, creates a comedic contrast that fits the absurd tone of the series.

His primary motivation is to defeat DMC in a musical competition, thereby proving the superiority of his own style and elevating his status in the underground music scene. He sees DMC, and especially its frontman Johannes Krauser II, as a direct obstacle to his own success. The attack on his fan serves as the catalyst that turns this rivalry into an open confrontation, and he seizes the opportunity to challenge the band publicly.

In the story, Kibayashi functions as a foil to Negishi. While Negishi is forced into a persona he despises and struggles to maintain his true identity, Kibayashi actively and willingly adopts a fake background to advance his career. Both characters are defined by the gap between who they pretend to be and who they actually are, but they respond to this duality in opposite ways. Kibayashi also represents the hip-hop side of the music industry within the series' satire, providing a counterpart to the death metal world of DMC.

His key relationships include his adversarial connection with Negishi and the DMC band members, rooted in both their childhood acquaintance and their current professional rivalry. His interactions with his own fans and crew, who support him in the battle, further establish his role as a leader within his own musical faction.

Regarding character development, Kibayashi does not undergo a major transformation over the course of the series. He remains a consistently antagonistic figure who serves his narrative purpose as a challenger to DMC. His role is more functional than developmental, as he is introduced to create a specific conflict and then recedes from the story once that conflict is resolved.

Notably, his abilities are centered on rapping and performance. He is skilled enough in his craft to command a following and to present himself as a legitimate threat to DMC in a musical battle. However, his actual talent is undermined by his fabricated backstory, suggesting that his credibility is at least partly a product of self-promotion rather than pure skill. His greatest ability may be his cunning and his willingness to use underhanded tactics to achieve his goals.