Kakure Tensei @comic

In a far-off corner of another world where only nobles can use magic, a certain thirty-something salaryman is reincarnated as a five-year-old village boy named Ren. For him, the slow-paced countryside life is peaceful and enjoyable—that is, until a group of adorable but terrifying little angels (a.k.a. troublemaking children) takes a liking to him. Even though he just wants to be lazy, he ends up doing things perfectly—like playing hide-and-seek from morning till night, reading stories aloud, and calming their wailing cries—because he's just too good at taking care of others! One day, while thinking of ways to slack off more, a monster suddenly attacks their once-peaceful village. And when the problem children are put in danger, the usually unmotivated Ren unleashes a hidden power he's kept secret—just to avoid getting dragged into more trouble! A laid-back reincarnated boy ends up babysitting (and saving the kingdom) in this reluctant hero's tale! (Source: TO Books, translated)