Hisano Kuroda is an old lady who establishes the Death Social Link. You will first meet Hisano while working part time at the local hospital and leveling up the Devil Social Link to Rank 4. The next Sunday, and every Sunday after, Hisano will appear at the Samegawa Flood Plain Riverbank. Speak with her to establish and rank up the Death social link.
Hisano will speak about her dead husband while ranking up the Social Link. At Rank 7, she will ask for some old letters of hers. Speak with Old Man Daidara at the Daidara Metal Works in the Central Shopping District, South to obtain the letters.