ShiGuang/Guangshi is the slash ship between Cheng Xiaoshi and Lu Guang from the Link Click fandom.
ShiGuang is the most popular ship in the Link Click fandom, and the ship has a decently big fanbase too. On AO3, it's the most written ship under the Link Click tag. With the events of Episode 11 though, HongShi has begun to emerge as a rival ship to ShiGuang. They are sometimes shipped with Qiao Ling in the poly ship, ShiGuangQiao.
The donghua itself has many ship tease moments, especially when they were forced to share ramen, and how Lu Guang hugged Cheng Xiaoshi (and bought him boba) even after the latter hit him in anger. Lu Guang also blushes occasionally when he's talking about Cheng Xiaoshi. Many fans love the ramen scene, because it sports many romantic undertones and leave a lot to fan interpretation. During a scene in "Emma", Cheng Xiaoshi and Lu Guang lie in alternate beds with the camera panning across both of them so it seems that they are together.