信不信我咬你啊那咬我的嘴行吗
[xìn bù xìn wŏ yăo nĭ a nèi yăo wŏ de zuĭ xíng ma]
The nickname implies a lighthearted and teasing tone, perhaps used in flirting context. It could be understood as: “Do you believe I will bite you? Would you then bite my lips if I do?”