That question makes Cu pause. He crosses his arms and leans against the wall. Enkidu makes a good point about Bonding with a Monster, and he will return to that later. But right now he's overcome with nostalgia for that long time spent at the end of the world with Ritsuka, Mash and others.

"Chaldea, huh. One hell of a good Master, made that place what it was-" Good times, good memories, it's a blessing he was allowed to keep those memories "Should they call on me again, I'm sure I will respond to it" the Heroic Spirit, Cu Chulainn that is. Another copy in a Servant vessel. Having already a different "him" around was always a good reminder of the workings of that system.

"All the time here, and i never thought that a 'me' that is 'me' here could truly return there- but you know what I thought?" It's a rhetoric question, he doesn't wait for an answer and follows immediately "If we're alive, that means our records, they could get updated, no? Maybe I can add something cool to my repertoire, imagine our Master's and others faces when they would see that".

But Caster you never could do that- ha, surprise, you have not seen everything of me yet!, A silly, but strangely hopeful scenario. Another way to make the best of their time here.