Grandmother Hasu

Nexus Guardian
Mahou has always been a gentle soul, but these past decades have been so full of tragedy, he has been taken over by his own grief and anger. It may not be too late for Mahou to excise these powerful demons, but he will need your help.

After completing the 'Anguish is the Worst' quest:

Nexus Guardian
Your work here is far from finished. I still expect Mahou to clean up the mess he's made - and I expect you to help. After all, you helped him create it, didn't you?

Location: Ghost Nexus

Thanks to Sorokage.