A brief description of the The Quintessential Quintuplets manga:
Since Fuutarou Uesugi, a high school student, is both poor and intelligent, he tries his hand at a job as a tutor that pays surprisingly well. The students he’s supposed to teach are his new classmate, Itsuki Nakano – including her four sisters. The quintuplets are not only chaotic, they also have absolutely no desire to learn, despite their miserable test results. But before they change for the better, Fuutarou first has to win the trust of the five sisters.