DXC is Yin-Yang.
Yin cannot live with-out Yang, Yang cannot live with-out Yin.Good can't live with-out Evil, Evil can't live with-out Good.
Yin-Yang means that Good always has has some sort of Evil and vise versa with Evil, Evil always has some sort of good in it.
Duncan & Courtney:
Duncan is bad, Courtney is good.There is some good in Duncan, and some evil in Courtney.Duncan can't live without Courtney, Courtney can't live with out Duncan.
They 愛 each other, My geuss well they will never leave each other.No matter how much one bugs the other.
Conclusion: Duncan&Courtney is Yin-Yang, I 愛 Yin-Yang.