Responses
He already did once before.
Ikr, liek why did u do it boy if you're gonna regret it for the rest of your life, in comparison to the fading belief you had to the brch proxy Saintess?
Spoiler.
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Ahuin did not have a choice. He, along with everyone else in the temple, is being brainwashed by the saintess to do whatever the saintess says.
Given the opportunity, I guess Ahuin still chose the will of the Saintess and harm his beloved.