Ok so that happends in older versions of your saves. recently the older save files kinda got corrupted(?) so when for example in my case it happened every time that richard appeared in my older harold route save file. ( ill guess that that happends because since richard got new sprites the names of the files of the images of richard changed, the older files cant find the correct sprites in that situation since older sprites had different names) so the only way i know that you can get rid of it is starting the route from the start in a recent/latest build of the game. (if i remember correctly dynewulf explained something related to older save files getting errors in a update log)