Miki owns and operates the Cat's Eye café, a key establishment within the series. She shares a significant history with Umibozu (Hayato Ijuin), having served alongside him as fellow soldiers during a Central American conflict. Their combat experiences evolved into a romantic relationship. After the war, Miki founded the café where Umibozu now frequently works as a waiter between his sweeper assignments. This location recurs as both a meeting place and operational base for series characters.