I know she does that if the player goes back to ACT I with her, but I haven't seen it ever in ACT II. The only thing I know of is that if she dies as a party member, other companions will trigger their mocking ACT I banter about her death. Like Shadowheart smirking about claiming Minthara's scalp as a trophy.
I like how you wax poetic about how much you love Larian, and then just casually reference an incredibly fucked-up mention of scalping that highlights Larian's philosophy of relishing in the slaughter and disrespect of non-white characters.
