After transmigrating to the Zhenguan era, Jiang Xian inherits a rundown tavern on the verge of closing.
His first customer calls himself Mr. Li, but the System reveals his identity: Emperor Taizong of Tang, Li Shimin.
Jiang Xian has no choice but to pretend he knows nothing while milking Li Er for emotional points, trading them for novel things the Tang dynasty has never seen.
Scallion-free pancakes, green plum drinks, little round mirrors... Each new item makes Li Er suspect there is more to Jiang Xian, yet Jiang Xian always manages to rile him up until he nearly chokes on his food.
Li Er: “I... I just came for a meal.”
Jiang Xian: “Sure. Pay first, sir.”
It looks good, there is a system to collect emotional values and exchange them for things, Li Shimin is not too smart, and the personalities of each character are well developed. It can be considered a relatively novel piece in the Tang Dynasty.
Don't look at it, it's full of AI flavor