Wolf & Parchment: New Theory Spice & Wolf, Vol. 9 (light novel) — Isuna Hasekura

Preparations for the ecumenical council have begun in earnest as Col and his companions think about who they should recruit to their cause. They will need all the help they can get to right the Church's wrongs, and there might be no better place to start than the imperial city of Estatt, as the archbishop who rules over it could be instrumental in making the emperor their ally. There's just one problem -- an imposter claiming to be the Twilight Cardinal has appeared just outside of Estatt and declared the city's cathedral a place of vice and greed. They have no idea what the imposter's goal is and even worse, Col isn't sure he can prove he's the real Twilight Cardinal…