The snow-bridge dialogue (Ch. 141 pp. 13-14) is the establishing scene of the Hiriluk-Kureha bond.
Kureha’s “we’ll meet again, young quack” parting is the chapter’s most ironic line: by the present-day frame, Hiriluk is dead and Kureha is keeping his mausoleum at Drum Castle.
The payoff
(Pending forward-canon — Hiriluk’s death-scene; Kureha’s adoption of Chopper; Kureha’s continued residence at Drum Castle as the mausoleum-keeper.)
The Ch. 140 ‘my reindeer’ possessive register from Kureha is now retroactively grounded — Chopper is the orphan-of-Hiriluk Kureha took in.
Why this matters
The bond is the structural through-line of every Kureha decision in the present-day arc:
Kureha is at Drum Castle (Ch. 0139+) because it is Hiriluk’s mausoleum.
Kureha has Chopper because Chopper was Hiriluk’s reindeer companion (Ch. 0141 flashback).