(…) Egged on by Archer, Kirei Kotomine, having awakened to the pleasures of depravity, leaves morality behind and satisfies his dark appetites. (…)  His unusual Master/Servant relationship with Archer could be said to be the show’s highlight. 

Ufotable on Team Archer.  Fate/Zero Blu-ray Disc Box II

Nothing else to say.

My Dad

We were chatting about the Fate series and he said something like: “I just really thought that Gilgamesh and the priest were going to have a romantic subplot. They kept flirting in Fate/Zero and then lived together for ten years. They should be married by now!”

He then went on to describe Gilgamesh and Kirei as “The most compatable team” and related them to Burt and Ernie.

He was also upset at Gilgamesh’s lack of emotion when he found out that Kirei died in UBW, but promptly blamed the evil Grail mud.

I was both laughing and agreeing the whole time. My father has found Yuetsu without me even saying anything.