Here you will find the best gifts for Fang, as well as Fang's entire list of loved, liked, neutral, disliked, and hated gifts. A great way to build relationship with Fang in My Time at Sandrock is by giving them their favorite gifts.
Fang
Although Fang can be both befriended and romanced, he refuses all gifts and friendship points cannot be gained through gifting. The only gift he will accept is a Heart Knot, which will start a relationship with him. Once you are a high enough relationship level Fang may also wish for items. If Fang has a desire you can fulfill it will be noted with a heart icon on the map.
You can chat with Fang once a day to get +1 friendship points. However, chatting with him more in the same day will just give you the same dialogue and won't increase your friendship points with him. You must first complete the quest "Taste of Your Own Medicine" before you can gain friendship points with him by chatting with him.