Shiinamachi-senpai no Anzenbi

Shiinamachi-senpai no Anzenbi summary:

“Today is my safe day, so please pay me a visit in my room.”
These bold words were addressed to me, Sakuradamon Jirou, from Shiinamachi Kaguya-senpai, a senior library monitor. Filled with antic.i.p.ation, I visited the “Clock Tower Caretaker’s Room” where Senpai lived, only to discover Senpai collapsed on the floor, all covered in blood. Then the situation proceeded to develop rapidly in an unexpected direction! The culprit is someone from around me? What secrets do Senpai harbor? Also, the truth about the past and the blood relations that I have kept hidden all these years and never told anyone, to think that–