Amarimonogatari

Araragi Koyomi's university arc (Monster Season) Oddities x Mystery "Do you still feel like playing detective?" From his kouhai at Naoetsu Highschool, Higasa Hoshiame, comes rumours of the kidnapping of an elementary school girl. Araragi Koyomi, now a first-year university student, along with Hachikuji Mayoi, Oshino Shinobu and Ononoki Yotsugi begin investigating, but...! This modern day oddity! Oddity! Oddity! In the Evening darkness, youth shines brightly. (Source: Kodansha, translated)

"It's an unfashionable monster. Even vampires are no match for them." Araragi Koyomi was consulted by his friend, Hamukai Meniko, about her falling out with her boyfriend. He himself had just been told by Hitagi Senjougahara that she is breaking up with him — along with an apology. Koyomi deduced that this commotion was the work of oddity. He goes to Oshino Ougi, an expert in the field of oddities. This modern day oddity! Oddity! Oddity! (Source: Kodansha, translated)