I really like the idea that Zhongli isn't affected by the cold (much) but Childe doesn't know that and when they visit Snezhnaya or Dragonspine he always worries about Zhongli and fusses over him, trying his best to make sure that Zhongli is warm and comfortable. And Zhongli realizes that he really likes the attention so he doesn't say anything and just goes along with it :3 ——— I like this too! Honestly, anything in which they're both caring for each other regardless of whether the other actually needs it or not is just everything to me. Childe protecting Zhongli from the cold, Zhongli fussing over even the smallest wounds and cuts on Childe despite him having plenty more where that came from...love it.