An OOC note, if your elf is not a pure high elf, they are not mali'aheral. Mali'aheral means blessed elf, not high elf. Therefore, if they are impure they are simply a high elf and lack any 'elven' designation except perhaps mali'tahu, which means high elf directly.
In the beginning, before your character even existed, it was used for all High Elves regardless of whether they were pure or impure. It will be impossible to change it now.
Not everyone knows this IC. A Human most likely wouldn't know the difference between a Mali'Tahu and a High Elf. So maybe they're just roleplaying well :P
