Responses
http://www.mangago.zone/read-manga/hanakoi_tsurane/sa/mpn_chapter-2024770/pg-6/
But here they confirmed that he's not dead...
See here: "That annoying gramps died already..."
http://www.mangago.zone/read-manga/hanakoi_tsurane/sa/sa-c001/27/
Wait so is the other grandpa alive (sorry i dont rmb names ╥﹏╥) ?