Seimii is the chief engineer tasked with maintaining and overseeing Dancouga Nova. She maintains a consistently flirtatious and playful demeanor, especially towards the pilots. Before every mission, she urges them to protect her "baby," revealing her deep personal attachment to the mecha. This intense emotional investment stems from past relationship difficulties; she endured a string of brief, unsatisfying romantic involvements. Consequently, she channels her emotional energy into Dancouga Nova, viewing it as a reliable entity incapable of causing her the pain human partners did.

This tendency surfaces notably when Sakuya requests a private conversation. Seimii initially interprets this as potential romantic interest. Her reaction shifts to visible disappointment and frustration upon learning his intentions were purely technical, concerning Dancouga Nova's systems. This incident highlights her persistent search for personal connection while simultaneously reinforcing her unwavering professional dedication to the mecha. Her character maintains this consistent focus throughout the series.