番茄你个偷马桶土豆你个陪他偷
[fān qié nĭ gè tōu mă tŏng tŭ dòu nĭ gè péi tā tōu]
This odd-sounding nickname translates to 'Tomato who steals the toilet, Potato who helps him.' It doesn't really have much meaning on the surface—it's an inside joke which can mean almost anything depending on context and shared experience. Usually it means something very silly.