Jigoku Shoujo Mitsuganae

Synopsis

Yuzuki returns a lost dog named Momo to her owner Mioi Hatsumi. Hatsumi's older neighbor Shintani shows off her new expensive bracelet but is insulted once she notices the same bracelet is worn by Momo as a collar. Shintani tries to get the apartment management to evict Momo. When this fails, she poisons the dog. Finding out that Shintani poisoned Momo, Hatsumi accesses the Hell website and confronts Shintani on the roof, unable to understand her hatred. Hatsumi ends up nearly falling off the roof. Trying to save herself, she accidentally pulls the string of her straw doll, sending Shintani to Hell, before falling. However, she survives.

(Source: Wikipedia)