Kare wa Superstar de Motokare de.

Mugi can't forget about her middle school boyfriend, Hiraga. Now that he's become the nation-wide famous actor Kouyou Yoshida, Mugi is certain he's forgotten about her. But when she goes to her school's 10-year reunion, she feels someone grab her hand. To her surprise, it's Hiraga! This is her reunited love with her ex-boyfriend who became a superstar.

(Source: Shogakukan, translated)