Himo Onee-san, Ezuke-chuu.

"Why don't you try keeping me?" Saki, who just moved to this town, has a secret: she is "keeping" the odd young woman who lives in the apartment next door. One day Saki, a middle schooler who loves to cook, finds the woman collapsed from hunger. Free-spirited and with zero life skills, the woman melts into a blissful smile at good food, and Saki just can't leave her alone... An unemployed onee-san and a serious middle-school girl share secret meals together! (Source: Shinchosha, translated)