"Ice and Fire" is a Bleach fanfic, CP: Shirashi (Hisugaya Toshiro and Kurosaki Kari).
As for the description of white pears, please check the Baidu Encyclopedia of white pears.
In addition, this article was also published on Baidu Tieba Baili Bar.
Most importantly, the authors of the second article are Zisonglian and Shuanghanxiaozi.
In other words, "Ice and Fire" is co-written by Zi Songlian and Shuang Han Xiaozi.