*I was supposed to be his protector… I didn't expect his smile to make my heart race—!* Naitou Kiyoko — a 179cm tall office lady, is admired by everyone like an older sister for her refreshing personality. When she was younger, she often dreamed of being a princess, but as she grew taller, she took on the role of protector for the girls around her. One day, Kiyoko's “dull” and “klutzy” kouhai Himeno Mikoto confides in her about his circumstances. Kiyoko, seeing Himeno's true worth, comes to a decision. I'll be there to protect you, Himeno-kun, so please stop hiding who you really are! And from that day onward, they start their new relationship as princess and protector…!? It's a cute, innocent, and heartwarming romcom about the headturner of a princess Himeno-kun, and his protector Naitou-san!