Disclaimer: I don't own XXXHolic or FGO along with their characters, each belongs to their respective creator Chaldea was very chaotic to begin with when a certain (former) shop owner was summoned and everything just got worse in the best way possible.

"There is a special providence in the fall of a sparrow. If it be now, 'tis not to come; if it be not to come, it will be now; if it be not now, yet it will come – the readiness is all. Since no man, of aught he leaves, knows what is't to leave betimes, let be. Oh. You're awake... formerly Servant Lancer." Diarmuid serves a new lord... a lord called Watanuki Kimihiro. Multi-Xover

Oneshot. Many years ago, Yuuko received a white-haired counter guardian on a stormy rainy day in Tokyo. What is he there for? Rin X Archer