What do you mean by China hamburger?

Intimate behavior. "Couples' Chinese hamburger" is a kind of network language, which refers to couples' excessive intimacy in public places, which is similar to an expression of "showing love". It turns out that "Chinese hamburger" is a traditional delicacy in Shaanxi, and two pieces of steamed bread are used to hold the meat. In network language, "meat" refers to one of the lovers, and "steamed bread" refers to the other, so "lovers are sandwiched in buns".