After he gets transformed into a vampire he has started to sand his fangs (4) but he reaches a point where he is trying to satisfy his bloodthirst. He looks at the people who pics up the trash, first thinking no one really would miss them. but doesn't feel attracted to them and convinces himself that they don't deserve to die. He hides somewhere else in the outskirts of the city and sees a well-looking man who at first doesn't recognize.  Hes alone and  River doesn't feel like killing him but he thinks he may be able to get some blood from him and leave without anyone seeing him. Approaches from behind and struggles with him but the man manages to see him. River recognizes him. He is one the guys from the army , of a higher rank and the one who he hates because is always making fun of him and being mean, treating him like an idiot. Despite this, now that he saw his face, he can't be left alive,  is River or him. After a fierce struggle River kills him and escapes , reaches an area  with a stela of the goddess tlazoltéotl, who is known to hear the confessions of dying men. 

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