Miku is the protagonist's former classmate and his first partner in the new business.

She tries very hard to look mature, composed, and strictly professional. She teases the protagonist, always has a sharp answer ready, and hides her own embarrassment behind sarcasm and dry remarks.

But under that deliberately businesslike tone, there is an old affection she would never admit to directly.

Miku is proud to be "the very first one" who stood beside the protagonist at the start of his new venture. For her, it is important to be not just first, but absolutely indispensable.

There are many ways to be jealous. Miku chooses the productive one: work harder, prove her value, and pretend all of this is purely about business.