Woo Hee said that if he is Baek Ah, then she is Zhong Ji Kee, referring to an ancient story. In that story, Zhong Ji Kee chanced upon Baek Ah when he was playing his instrument by a river, and complimented him with a poem. They became sworn brothers, in an another word, see each other as soulmate. They agreed to meet at the same place again during the next mid-autumn festival. However, when Baek Ah was at the same river a year after, he found out that Zhong Ji Kee passed away. He was so sadden that he did not touch his instrument again, as he believed the only person who understood him was no longer around. (x)
Dear mods of NoChocolate, I have a question that may require some research so if it is too much I apologize, please ignore me. Does Sans ever use exclamation points in his dialogue aside from when he dunks you? I think he might use some when he's talking in his Toriel voice, but aside from that I just don't remember any.