Aoharu Danante Kimi no Sei

Ena, a high school girl, is working part-time as a housekeeper. Her new customer, Mikanagi-san, is a manga artist. Mikanagi, who seems so cool and unapproachable, suddenly asks Ena to “teach him to JK” to help with the manga he's working on. Now they do things like go out to the beach and take purikura pictures together. But is this all suppose to be part of the job? Because this close relationship is getting her all flustered! A love story between a cool and handsome guy and his “youth teacher" is about to begin!

(Source: Comic Days, translated)