The Devil Is a Part-Timer!, Vol. 4 (manga)
Available for back-order
This complication wears a kimono! The arrival of Suzuno Kamazuki has made everybody's life more complicated! After some misunderstandings regarding Suzuno's intentions toward Maou are cleared up, Emi asks for her help to...defeat the Devil King?! Meanwhile, a shadowy assailant continues to stalk Emi, but what does he--or she--want?