Watari-kun no xx ga Houkai Sunzen

Since his parents’ deaths, Nao Watari has devoted himself to caring for his little sister. He gives up club activities to spend time with her, and his classmates call him a siscon. Nao is prepared to ignore their remarks as long as his sister is happy. But a threat from six years ago has returned, putting the life he has built at risk. It comes in the form of a girl carrying a garden hoe, determined to reclaim what she once considered hers alone.