the good news is i was able to replicate the crash, but only by equipping a GF, opening the dresser, tabbing over to the GF's page, exiting the menu, dismissing the GF, and then reopening it. the menu seems to remember it wants to be on the GF's tab who doesn't exist anymore, so the "Equipped!" text in the list is referencing noone "[-4] out of range [character_list]".. I don't think that's what you did since it seems to have caught you immediately, but the crash point is exactly the same, (menu draw line 111 (call entry value text); calling script line 101 (text's entry owner); calling script line 21 (fetch current char's palette)
This should be easy to patch up, I'll try and get something up tonight.
Thank you for the report!
(edit (first few were trying to attach my crash image), but the build is up now, sorry for the trouble)