Kiben Gakuha, Yotsuya-senpai no Kaidan.

Yotsuya-senpai, a mysterious student at an ordinary school who solves supernatural cases...only if you pay him with a good horror tail! Desperate to find her missing friend, Nakashima Makoto turns to the legend for help...What ties their search to the string of brutal child murders haunting the headlines? Two unlikely partners. One chilling truth. The mystery starts here. (Source: MANGA MILLION) Note: Include the one-shots "Asobiba," "Ousama Kid" and the pilot one-shot.