The Devil Is a Part-Timer! High School!, Vol. 5 — Satoshi Wagahara

Having been banished to modern-day Japan to attend high school, the Devil King (Maou) and the Hero (Emi) have been fighting a high-stakes battle to control the student council! When Maou manages to win, the defeated Emi feels a terrible pang in her chest for...Maou?! Surely not! Did the high school foibles of these fated rivals just get a lot more complicated?