14 year old assassin code named Glass Heart from the Suzacu unit doesn't want to kill anymore. Every time she kills her heart breaks and all she wants is to break free. Will her answer to her problems be the right one and solve all her problems like she wants. She’s not a lost cause yet and one year later Glass Heart is about to learn what her heart truly wants. Meanwhile somewhere else another broken heart wonders the streets. After an accident his fiance was involved in one year ago he wonders if his life will ever be the same.

Given a new chance to live Glass Heart escapes from the surgery and decides to seek the meanings of her visions. She must find Saeba Ryo but when she gets to Shinjuku she finds it hard to leave old habits like killing behind as her heart is not made of glass anymore. Will she find what she is seeking without losing herself in memories that dont belong to her and the places which are familiar to a part of her but she has never been to.