It's a running theme of characters going "hey I am literally a monster, I am fundamentally humanity's enemy, I am evil and rotten to the core, how can you stand to work with me?" and Guda responds with "Anyways." (Gorgon's interlude, Yu Meiren's valentine, lb7). Which is probably for comedic purposes, but I do find it fascinating that Guda's first reaction to these statements is to completely change the subject. They basically need to be pressured into a corner to give an actual justification (being "idc what you are, you're standing by my side and that's what matters.") Is it that they don't want to think about what their companions are? Is it that they consider the very question absurd and unworthy of a real answer? Is it that they don't know how to react? Is it that they're tired of having this conversatino with every god and monster in Chaldea?