Yuureitou

In the 1950s, an old woman was brutally murdered on the face of a clock tower by her adopted daughter. Two years later, the clock tower is known as the 'ghost tower' and it is supposedly haunted. Through an unusual series of events, a young NEET man named Amano Taichi is attacked by someone or something in the same clock tower, and finds himself bound to the clock face to be killed in the same way as the old woman. Luckily for Amano, he doesn't meet the same fate. He's rescued by a mysterious person who claims his name is Tetsuo.
(Source: MangaHelpers)