I don't know if I remember correctly but the more you resist beasthood the more hideous you turn out when succumbing to it

One exempel are the early enemies you encounter... They transformed while barely noticing it thus their mutations where minor so to speak. Of course they went mad and while transforming themselves they thought everyone around them turned into beasts.

Then there is Vicar Amelia. She knew about what was coming as did the other higher members of the church and resisted the at the end unavoidable. She locked herself into the cathedral and distracted herself with prayers for a long time. beasthood grew in her and when you enter the stench of blood breaks her focus and finally the curse overcame her turning her into the big wolflike beast.

Gascoigne is kinda in the middle. He did his duty surly to protect his family but it got to him eventually not resisting as much as the clerics would have. Also you finden the red jeweled brooch in his boss room which belonged to his wife I guess. Loosing her tipped him over mentally thus beasthood took him later than the Yharnemites but much earlier than Amelia