Katsumi Karasawa directs Border’s external affairs and business departments, orchestrating negotiations and securing funding across municipal, national, international, and inter-dimensional spheres. His pragmatic diplomacy prioritizes resource utilization over conflict, engaging entities from the Neighborhood to advance strategic interests.

Physically, he sports short brown hair slicked back, brown eyes, and a suit with thin black stripes, later layered with a sweater during the Black Trigger Retrieval Arc. A cigarette often rests in hand, his arched eyebrows signaling curiosity or surprise. A rugby-forged athleticism persists in his physique, evident when mobilizing rubble during crises.

Reserved yet analytical, he listens intently before speaking, leveraging an acute understanding of others’ motives to navigate dialogues—even with inter-dimensional beings. He admires those like Osamu Mikumo, whose unwavering principles yield outsized impacts despite risks, aligning with his self-labeled “greed” for tangible results over abstract ideals.

Colleagues witness his understated support, such as urging Yūichi Jin to guide struggling apprentices. His dual role straddles financial pragmatism and inter-dimensional diplomacy, though departmental boundaries remain undefined. Personal preferences include cigarettes, rugby, pollock roe, and kamameshi rice dishes.

No concrete details regarding his background, character development in additional media, or involvement in spin-offs or films are provided.