Mika Hayamura

Mika stands at about average height and wears her hair to a middle length. Her usual outfit is a simple sweater dress.

Mika is direct and willing to stand her ground. She scolds Yoma over the hazards and expenses his obsession creates, presses him to return the money he took, and warns that she will bring in the police if he refuses to leave. In calmer moments she also shows patience and care, praising how fast his body is changing and cooking for the two of them.

As Yoma sinks deeper into his fitness compulsion, Mika trips over the weights he leaves scattered on her apartment floor and begs him to clear them away. She remarks with genuine surprise on how quickly his muscles have filled out. Her cooking goes to waste when he refuses the walleye pollock roe pasta she prepares because he is cutting carbs, and his broken plans leave her apologizing to a delivery worker whom he had threatened to kill.

Later she catches him bouldering across the walls of her cramped room and decides he has lost his mind. She insists he pay back the 270,000 yen he charged to her card and threatens to phone the authorities. Rohan eventually reads the truth through Heaven's Door: on October 26, Yoma snapped her neck and sealed her body inside the walls of the room in cement.