ERU

Christmas season. Hasegawa Y?ta found himself single after breaking up last month when his girlfriend had cheated on him. And it was only a few days until Christmas! After an everyday conversation with his female friend, Mino Ayaka, Y?ta met a beautiful girl clad in a Santa suit—In a lane full of couples no less! Her name was Shinohara Mayu. Will this encounter with Shinohara turn out to be the Christmas present for Y?ta ?

Eguchi Hibiki is a manga artist who has knowledge but no understanding of erotica. While wondering what exactly erotica is, Hibiki meets Yasaki Mia, a succubus who is also wondering about erotica. The two are somewhat similar and decide to work together to understand "true erotica."