Vahn was aware of the puppy love that Kamiya had developed for Mordred, but, after discussing it with Artoria and Nobunaga, he decided to let the matter run its course. They weren't blood-related, and, before Mordred began to 'aggressively' pursue him, Vahn wouldn't have been too troubled if they ultimately ended up together. While some might see it as 'grooming', Mordred possessed no such intentions towards her step-sibling, so, if something did develop between them, it would have been the result of Kamiya's adolescence, not direct manipulation.
Endless Path : Infinite Cosmos
Anime & Comics · Einlion
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