Nishimura-kun is a recurring character in the anime Alice SOS. He is a boy approximately the same age as the protagonist, Takashi, and is characterized by his use of an effeminate, campy manner of speaking. Throughout the series, Nishimura-kun appears repeatedly in various disguises, often at critical moments during Takashi and his friends' journey to rescue Alice. His true intentions are deliberately kept ambiguous; the advice he offers sometimes proves genuinely helpful and rescues the group from danger, yet at other times it leads them into traps or worsens their predicament. Because of this inconsistency, it is never clearly established whether Nishimura-kun is a friend or an enemy. However, it is implied that he is not a direct servant of the Devil Boss, the main antagonist. His motivations seem to be tied to a personal interest in Takashi, whom he appears to like, and this affection may drive his unpredictable actions rather than any loyalty to a larger cause.

Personality-wise, Nishimura-kun is secretive, playful, and enigmatic. He does not openly confront the protagonists but instead toys with them through his disguises and cryptic guidance. His role in the story is that of a wildcard: he can shift the momentum of an episode in either direction, adding an element of uncertainty to the adventure. He does not display notable combat abilities or special powers; his primary skills are disguise and manipulation. In terms of key relationships, the most significant is his connection to Takashi, which seems to be the catalyst for his repeated appearances. The series does not provide any development or resolution for Nishimura-kun; he remains a mysterious figure whose background, true name, and ultimate goals are never revealed. His presence serves to keep the audience guessing and to complicate the protagonists' already difficult quest.