Hasty morning thought on Saiyuki, volumes 1-9. No Reload spoilers, please.
So, the Sanko ikkou and the Kougaiji ikkou (and someone please tell me how you actually pronounce those in Japanese, because now I have "ikou ikou inay" stuck in my head). Four each, in opposition, pairs among them carefully set up.
Gojyo and Jien? Brothers.
Hakkai and Yaone? Similar roles and personalities (at least superficially); intertwined backstories.
Goku and Kou? Zen moments of challenge and understanding; once and future prisoners.
Which leaves us with . . . Sanzo and Lirin.
Just comic relief, or something else I'm not seeing?