Hisui Soda no Awa ni Nosete

Anka, a high-school girl whose favorite drink is the melon-soda ice-cream float, is invited by her super free-spirited senior, Tsutomu, to work part-time at her kissaten cafe, with all the soda she can drink as bait. A soothing cafe comedy! (Source: Manga Time Kirara Carat, translated)