Yuusha Uchuu Sworgrader

The story revolves around Taira Yunokami, a boy in fifth grade who helps his father run a food truck. One day, he meets a famished girl in a park on his way to school. After helping the girl, the city is suddenly attacked by Glutton, an inter-dimensional threat that endangers the world. Amidst the chaos, Sworg, a young member of the Space Administration Bureau Braver, saves both Taira and the girl. Sworg has come to Earth to pursue the enigmatic and malevolent Glutton. When fate brings Sworg and Taira together, they'll find themselves unexpectedly thrust into an extraordinary journey through multiple dimensions.

(Source: Mangadex)