Kurokami Seiso no Reikoku Bishoujo o Tasuketara, Ore to Futarikiri no Toki dake Dereru You ni Natta Ken
After I Rescued a Cold-Hearted, Black-Haired, Beautiful Girl, She Started Acting Sweet Only When We Were Alone / After I Saved the Cold Princess, She Only Acts Sweet to Me When We're Alone / Kurokami Seiso no Reikoku Bishoujo wo Tasuketara, Ore to Futarikiri no Toki Dake Dereru You ni Natta Ken / 黒髪清楚の冷酷美少女を助けたら、俺と二人きりの時だけデレるようになった件 / Kurokami Seiso no Reikoku Bishoujo wo Tasuketara, Ore to Futarikiri no Toki dake Dereru you ni Natta Ken
At Seiryo High School, where second-year student Minato Ichijo attends, there is a girl known as the “Cold Princess.” Her name is Rei Nanase. With her stunning beauty and exceptional talents, many admire her—yet she rejects all advances with an icy attitude. Minato, however, has little interest in romance due to personal reasons. Even though Rei sits next to him in class and works part-time at the same café, he pays her no special attention. One day, Minato stumbles upon Rei in a back alley, quarreling with a persistent man he recognizes as a customer who had been turned down by her at the café. Acting on impulse, he steps in to help. The very next day after work, Rei unexpectedly appears in the staff room—despite not being scheduled—and suddenly demands a kiss from Minato… Thus begins Minato’s bewildering days, swept up by a slightly offbeat kuudere young lady. (From MangaDex)