I don't like PvP, but aside from ganging up on Duelists or Ring'd fight clubs, I will fight as my Host requires of me.
In case of curiosity, I always mark the fallen with Rainbow Stones and pay them respects, regardless if they were toxic or not. I do the same for slain bosses as well. Did the same in DS3 as well. Regardless of how the invader played, I shall respect their efforts in murdering the Host by any means by marking their grave.
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