Mutsumi Sakurano works as a waitress at Bosom Valley Hot Springs.
Mutsumi is a classic tsundere character. She can be shown to be cold or have burst of anger toward people (more specifically Takeshi). However, she can also be warm to those she likes as long as she's not pushed to far.
Originally, she did not like Takeshi do to his perverted nature and desire to peak on women bathing. After seeing his more noble side, she tried to warm up to him only to be turned down because he was watching porn. He later apologized and they reconciled through sex. Despite occasional sex, she can still be very annoyed with his antics.