Curate, connect, and discover
Here are a few characters who I interpret as aspec:
Dinadan!!! He is an absolute aroace icon. In a source whose name has slipped my mind, Isolde comments on how he ought to be in a relationship and his reaction is something along the lines of, “Yeah, hard pass. How’s that working out for you, by the way?” (Read it with sarcasm).
Galahad, Bors, and the Grail Heroine all seem quite happy about the eternal chastity thing. None of them have any close calls with demon ladies, unlike poor Percival, the one allo person in the friend group. (Yes, Bors has a son, but a cursed ring was involved there, which is why as much as I do not stand Bors’ Morte misogyny, I will always pity him).
Kay is very rarely ascribed romantic relationships, and in one Welsh source, his father prophesies that Kay’s heart will be “eternally cold”, which could be interpreted as never enflamed by love.
Any others who come to mind?