Momoko Kakehashi teaches at Satogahama High School. When students approach her to form a baseball team, she supplies the initial application form to establish their association. After the group recruits enough members to become an official club, she volunteers as the advisor. In this role, she secures a dedicated room for club meetings and activities. She also alerts the team to an available baseball field for practice, though it requires extensive cleanup due to overgrown grass and lies far from the school.

She has dark-brown hair braided on the left side and green eyes. Her height is 1.63 meters, and her weight is 54 kilograms. Her birthday falls on September 3. Her surname "Kakehashi" uses the characters for "hang/suspend" (掛) and "bridge" (橋), while her given name "Momoko" combines "peach" (桃) and "child" (子).