When a man and a woman are fornicating and the man sticks a zuccini up her bum. He cuts off the other half, puts it in his mouth, and sticks it in the frontal region. While eating her out she has to shoot both of them out simultaneously, and try to get one half back into his mouth. For this to be a proper 'Welsh Zuccini' the man, or woman, must be of Welsh origin.
Zustin is a outgoing and very fun to be around person. Though his face may not be the best you will likely enjoy him in bed. He also has an amazing body to go along with his personality.
Girl: “Damn he’s got a nice body”.
Girl 2: “His name must be zustin”.