不用葷 This Poor Monk Eats No Meat
妖精挽著三藏，行近草亭道：「長老，我辦了一杯酒，和你酌酌。」唐僧道：「娘子，貧僧自不用葷。」妖精挽着三藏，行近草亭道：「长老，我办了一杯酒，和你酌酌。」唐僧道：「娘子，贫僧自不用荤。」
逐句解 Line by line
The fiend drew Tripitaka along and came up to the thatched pavilion, saying, "Elder, I have set out a cup of wine, and mean to take a drink with you."
The invitation is domestic and perfectly polite, which is what makes it dangerous. 著 is zhe, the reading for an action held in place, so she does not take his arm once — she keeps hold of him the whole way. 酌 doubled is the modest word for taking a drink together.
The Tang Monk said, "Madam, this poor monk has never taken meat."
葷 is the class of foods forbidden to a Buddhist — flesh, and also the pungent vegetables of the onion family, which were held to inflame the passions. He is refusing on the narrowest available ground, which is the ground he has, and she is about to close it off.
Tripitaka's objection is technically correct and tactically hopeless. He has reached for the rule that fits, and the rule is about food. She has already arranged for the food to comply.
The forbidden class is broader than English meat suggests and the breadth matters. Garlic, onion and their relatives were banned alongside flesh on the reasoning that they heat the blood and stir desire. The vegetarian banquet upstairs is therefore not a concession but a strategy: she has removed his only stated objection while leaving the real one untouched.