Toshiue Elite Onna Kishi ga Boku no Mae de dake Kawaii  

Older elite knight is cute only in front of me, 年上エリート女騎士が僕の前でだけ可愛い

In history, there has been no other prodigy as exceptional as Haru, who has been assigned to the knights of the king at just sixteen years old. Karen, at twenty nine years old and single, leads this elite order of the fiercest men in the kingdom as its captain. Despite her fearsome reputation as "Demon Knight Captain," she shows her softer side when she invites him to her room, pampering him with special treatment only for him.