Why is killing Wei called Riyue cp?

One is like the sun and the other is like the moon. Killing Wei refers to Sesshomaru and Ge Wei. One of them is like the sun and the other is like the moon, which is called the sun and moon CP. "Inuyasha" is a long cartoon with the theme of describing the myths and stories of the Warring States Period, which was serialized by the famous Japanese cartoonist Rumiko Takahashi in the magazine "Weekly Youth Sunday" from 65438 to 0996.